Editing Letter case

{{short description|Uppercase or lowercase}}
{{redirect-multi|3|Lowercase|Uppercase|Capital Letters|the musical style|Lowercase (music)|the magazine|Uppercase (magazine)|the song|Capital Letters (song)}}
{{more citations needed |date=December 2023}}
[[File:A (capital and small).svg|thumb|159px|The lower-case "a" and upper-case "A" are the two case variants of the first letter in the [[English alphabet]].]]
'''Letter case''' is the distinction between the letters that are in larger '''uppercase''' or '''capitals''' (more formally ''[[#Majuscule|majuscule]]'') and smaller '''lowercase''' (more formally ''[[#Minuscule|minuscule]]'') in the written representation of certain languages. The [[writing system]]s that distinguish between the upper- and lowercase have two parallel sets of letters: each in the majuscule set has a counterpart in the minuscule set. Some counterpart letters have the same shape, and differ only in size (e.g. {{angbr|C, c}} {{angbr|S, s}} {{angbr|O, o}} ), but for others the shapes are different (e.g., {{angbr|A, a}} {{angbr|G, g}} {{angbr|F, f}}). The two case variants are alternative representations of the same letter: they have the same name and [[pronunciation]] and are typically treated identically when sorting in [[alphabetical order]].

Letter case is generally applied in a mixed-case fashion, with both upper and lowercase letters appearing in a given piece of text for legibility. The choice of case is often denoted by the [[grammar]] of a language or by the conventions of a particular discipline. In [[orthography]], the uppercase is reserved for special purposes, such as the first letter of a [[Sentence (linguistics)|sentence]] or of a [[proper noun]] (called capitalisation, or capitalised words), which makes lowercase more common in regular text.

In some contexts, it is conventional to use one case only. For example, [[Engineering drawing|engineering design drawings]] are typically labelled entirely in uppercase letters, which are easier to distinguish individually than the lowercase when space restrictions require very small lettering. In [[mathematics]], on the other hand, uppercase and lowercase letters denote generally different [[mathematical object]]s, which may be related when the two cases of the same letter are used; for example, {{mvar|x}} may denote an element of a [[set (mathematics)|set]] {{math|''X''}}.

==Terminology==
{{multiple image
| direction = vertical
| width = 250
| image1 = Upper case and lower case types.jpg
| caption1 = Divided upper and lower type cases with cast metal [[Sort (typesetting)|sort]]s
| image2 = UPPER CASE - lower case.jpg
| caption2 = Layout for type cases
}}

The terms ''upper case'' and ''lower case'' may be written as two consecutive words, connected with a hyphen (''upper-case'' and ''lower-case''{{Snd}}particularly if they [[Compound modifier|pre-modify]] another noun),<ref name="Bloomberg" /> or as a single word (''uppercase'' and ''lowercase''). These terms originated from the common layouts of the shallow [[Drawer (furniture)|drawers]] called ''[[type case]]s'' used to hold the [[movable type]] for [[letterpress printing]]. Traditionally, the capital letters were stored in a separate shallow tray or "case" that was located above the case that held the small letters.<ref name="Typographia, an Historical Sketch of the Origin and Progress of the Art of Printing">{{cite book|last1=Hansard|first1=Thomas Curson|title=Typographia, an Historical Sketch of the Origin and Progress of the Art of Printing|date=1825|pages=[https://archive.org/details/typographiaanhi01hansgoog/page/n470 408], 4806|url=https://archive.org/details/typographiaanhi01hansgoog|access-date=12 August 2015}}</ref><ref>{{cite book|title=Medieval Calligraphy: Its History and Technique|author=Marc Drogin|url=https://books.google.com/books?id=oHNtDQAAQBAJ&pg=PA37|page=37|publisher=Courier Corporation|year=1980|isbn=9780486261423}}</ref><ref>{{cite video|title=Ever wonder where upper case and lower case comes from?|author=Sacramento History Museum|url=https://www.facebook.com/reel/1055625212296596}}</ref>

===Majuscule===
'''Majuscule''' ({{IPAc-en|ˈ|m|æ|dʒ|ə|s|k|juː|l}}, less commonly {{IPAc-en|m|ə|ˈ|dʒ|ʌ|s|k|juː|l}}), for [[Paleography|palaeographers]], is technically any script whose letters have very few or very short [[Ascender (typography)|ascenders]] and descenders, or none at all (for example, the majuscule scripts used in the [[Codex Vaticanus Graecus 1209]], or the [[Book of Kells]]). By virtue of their visual impact, this made the term majuscule an apt descriptor for what much later came to be more commonly referred to as uppercase letters.

===Minuscule===
{{redirect|Minuscule}}
'''Minuscule''' refers to lower-case letters. The word is often spelled ''miniscule'', by association with the unrelated word ''miniature'' and the prefix ''mini-''. That has traditionally been regarded as a spelling mistake (since ''minuscule'' is derived from the word ''minus''<ref name="Lewis 1890" />), but is now so common that some [[dictionaries]] tend to accept it as a non-standard or variant spelling.<ref name="AHD 2000" /> ''Miniscule'' is still less likely, however, to be used in reference to lower-case letters.

==Typographical considerations==
The [[glyph]]s of lowercase letters can resemble smaller forms of the uppercase glyphs restricted to the baseband (e.g. "C/c" and "S/s", cf. [[small caps]]) or can look hardly related (e.g. "D/d" and "G/g"). Here is a comparison of the upper and lower case variants of each letter included in the [[English alphabet]] (the exact representation will vary according to the [[typeface]] and [[font]] used):

{| style="margin-left:1.5em;text-align:left;"
|-
!style="padding:0 1.0em;"| Uppercase
| A || B || C || D || E || F || G || H || I || J || K || L || M || N || O || P || Q || R || S || T || U || V || W || X || Y || Z
|-
!style="padding:0 1.0em;"| Lowercase
| a || b || c || d || e || f || g || h || i || j || k || l || m || n || o || p || q || r || s || t || u || v || w || x || y || z
|}

(Some lowercase letters have variations e.g. a/ɑ.)

[[Typography|Typographically]], the basic difference between the majuscules and minuscules is not that the majuscules are big and minuscules small, but that the majuscules generally are of uniform height (although, depending on the typeface, there may be some exceptions, particularly with ''Q'' and sometimes ''J'' having a descending element; also, various [[diacritic]]s can add to the normal height of a letter).

[[File:Typography Line Terms.svg|thumb|300px|Ascenders (as in "h") and descenders (as in "p") make the height of lower-case letters vary.]]

There is more variation in the height of the minuscules, as some of them have parts higher ([[Ascender (typography)|ascenders]]) or lower ([[descender]]s) than the typical size. Normally, ''b, d, f, h, k, l, t''{{NoteTag|name=ad|In [[Antiqua (typeface class)|Roman Antiqua]] or other vertical fonts, the defunct [[long s]] (ſ) would have been an ascender; however, in italics, it would have been one of only two letters in the [[English alphabet]] (and most other [[Latin-script alphabets]]) with both an ascender and a descender, the other being ''f''.<ref name="Nesbitt">{{cite book | title = The History and Technique of Lettering | first = Alexander |last = Nesbitt | edition = 1st | publisher = Dover Publications | year = 1957 | location = New York City | isbn = 0-486-20427-8 |url=https://archive.org/details/historytechnique0000nesb_r0f7}}</ref>}} are the letters with ascenders, and ''g, j, p, q, y'' are the ones with descenders. In addition, with [[Text figures|old-style numerals]] still used by some traditional or classical fonts, ''6'' and ''8'' make up the ascender set, and ''3, 4, 5, 7'', and ''9'' the descender set.

==Bicameral script==
{{original research|section|date=April 2015}}
[[File:Fountain pen writing (literacy).jpg|thumb|250px|[[Handwritten]] Cyrillic script]]
[[File:Adyge alphabet 1927 (1).JPG|thumb|250px|[[Adyghe language|Adyghe]] Latin alphabet, used between 1927 and 1938, was based on Latin script, but did not have capital letters, being unicameral ([[small caps]] include ᴀ, ʙ, ᴣ, ʀ, {{Smallcaps|{{lc:Ⱪ}}}}, ᴘ, and [[File:Latin letter small capital P with bottom hook.svg|x8px]].]]

A minority of writing systems use two separate cases. Such writing systems are called ''bicameral scripts''. These scripts include the [[Latin alphabet|Latin]], [[Cyrillic script|Cyrillic]], [[Greek alphabet|Greek]], [[Coptic alphabet|Coptic]], [[Armenian alphabet|Armenian]], [[Glagolitic script|Glagolitic]], [[Adlam alphabet|Adlam]], [[Warang Citi]], [[Old Hungarian alphabet|Old Hungarian]], [[Garay alphabet|Garay]], [[Zaghawa script|Zaghawa]], [[Osage alphabet|Osage]], [[Vithkuqi alphabet|Vithkuqi]], and [[Deseret alphabet|Deseret]] scripts. Languages written in these scripts use letter cases as an aid to clarity. The [[Georgian alphabet]] has several variants, and there were attempts to use them as different cases, but the modern written [[Georgian language]] does not distinguish case.<ref>{{Citation |last=Březina|first=David|date=2012|title=Challenges in multilingual type design|pages=14|via=University of Reading Department of Typography and Design}}</ref>

All other writing systems make no distinction between majuscules and minuscules{{Snd}} a system called unicameral script or [[unicase]]. This includes most [[Syllabary|syllabic]] and other non-alphabetic scripts.

In scripts with a case distinction, lowercase is generally used for the majority of text; capitals are used for capitalisation and [[Emphasis (typography)|emphasis]] when [[font weight|boldface]] is not available. [[Acronym]]s (and particularly initialisms) are often written in [[All caps|all-caps]], depending on [[Acronym#Case|various factors]].

===Capitalisation===
{{Main|Capitalisation}}
Capitalisation is the [[writing]] of a [[word]] with its first [[letter (alphabet)|letter]] in uppercase and the remaining letters in lowercase. Capitalisation rules vary by [[language]] and are often quite complex, but in most modern languages that have capitalisation, the first word of every [[Sentence (linguistics)|sentence]] is capitalised, as are all [[proper noun]]s. {{citation needed|date=October 2015}}

Capitalisation in English, in terms of the general orthographic rules independent of context (e.g. title vs. heading vs. text), is universally standardised for [[formality|formal]] writing. Capital letters are used as the first letter of a sentence, a proper noun, or a [[proper adjective]]. The [[names of the days of the week]] and the names of the months are also capitalised, as are the first-person [[pronoun]] "I"<ref name="Oliver #1">{{cite web | url = http://www.eslcafe.com/grammar/using_capital_letters01.html | title = Using Capital Letters (#1) | author = Dennis Oliver | website = Dave's ESL Cafe | access-date = 19 February 2017 }}</ref> and the [[Vocative case#English|vocative particle]] "[[wikt:O#Particle|O]]". There are a few pairs of words of different meanings whose [[list of case sensitive English words|only difference is capitalisation]] of the first letter. [[Honorific]]s and personal [[title]]s showing rank or prestige are capitalised when used together with the name of the person (for example, "Mr.&nbsp;Smith", "Bishop Gorman", "Professor Moore") or as a direct address, but normally not when used alone and in a more general sense.<ref>{{cite web | url = http://web.mnstate.edu/hanson/MC210/MC210_AP_titles.htm | title = AP Style: Courtesy and Professional Titles | author = Nancy Edmonds Hanson | website = Minnesota State University | date = 25 August 2008 | access-date = 19 February 2017 | archive-date = 1 December 2016 | archive-url = https://web.archive.org/web/20161201184205/http://web.mnstate.edu/hanson/MC210/MC210_AP_titles.htm | url-status = dead }}</ref><ref>{{cite web | url = http://englishplus.com/grammar/00000049.htm | title = Capitalizing Titles of People | website = English Plus | date = 1997–2006 | access-date = 19 February 2017 }}</ref> It can also be seen as customary to capitalise any word{{Snd}} in some contexts even a pronoun<ref>{{cite web | url = http://www.chicagomanualofstyle.org/qanda/data/faq/topics/Capitalization/faq0004.html | title = Capitalization | website = The Chicago Manual of Style Online | access-date = 19 February 2017 }}</ref>{{Snd}} referring to the [[deity]] of a [[Monotheism|monotheistic religion]].

Other words normally start with a lower-case letter. There are, however, situations where further capitalisation may be used to give added emphasis, for example in headings and publication titles (see below). In some traditional forms of poetry, capitalisation has conventionally been used as a marker to indicate the beginning of a [[Line (poetry)|line of verse]] independent of any grammatical feature. In political writing, parody and satire, the unexpected emphasis afforded by otherwise ill-advised capitalisation is often used to great stylistic effect, such as in the case of George Orwell's [[Big Brother (Nineteen Eighty-Four)|Big Brother]].

Other languages vary in their use of capitals. For example, in [[German language|German]] all nouns are capitalised (this was previously common in English as well, mainly in the 17th and 18th centuries), while in [[Romance languages|Romance]] and most other European languages the names of the days of the week, the names of the months, and adjectives of nationality, religion, and so on normally begin with a lower-case letter.<ref>{{cite web | url = http://libguides.dickinson.edu/c.php?g=56073&p=1112966 | title = Citing Sources: Capitalization and Personal Names in Foreign Languages | website = Waidner-Spahr Library | publisher = Dickinson | access-date = 30 March 2017 }}</ref> On the other hand, in some languages it is customary to capitalise [[T–V distinction|formal polite pronouns]], for example {{lang|da|De}}, {{lang|da|Dem}} ([[Danish language|Danish]]), {{lang|de|Sie}}, {{lang|de|Ihnen}} (German), and {{lang|es|Vd}} or {{lang|es|Ud}} (short for {{lang|es|usted}} in [[Spanish language|Spanish]]).

Informal communication, such as [[texting]], [[instant messaging]] or a handwritten [[sticky note]], may not bother to follow the conventions concerning capitalisation, but that is because its users usually do not expect it to be formal.<ref name="Oliver #1" />

===Exceptional letters and digraphs===
* The German letter "[[ß]]" formerly existed only in lower case. The orthographical capitalisation does not concern "ß", which generally does not occur at the beginning of a word, and in the all-caps style it has traditionally been replaced by the [[Digraph (orthography)|digraph]] "SS". Since June 2017, however, [[capital ẞ]] is accepted as an alternative in the all-caps style.<ref>Cf. {{citation|first=Kerstin |last=Güthert |url=http://www.rechtschreibrat.com/DOX/rfdr_PM_2017-06-29_Aktualisierung_Regelwerk.pdf|title=PRESSEMITTEILUNG 29.6.2017 Amtliches Regelwerk der deutschen Rechtschreibung aktualisiert |publisher=[[Council for German Orthography]] |access-date=2017-06-29 |year=2017 |page=1}}.</ref> 
* The Greek upper-case letter "[[Sigma|Σ]]" has two different lower-case forms: "ς" in word-final position and "σ" elsewhere. In a similar manner, the Latin upper-case letter "[[S]]" used to have two different lower-case forms: "s" in word-final position and "<big> ſ </big>" elsewhere. The latter form, called the [[long s]], fell out of general use before the middle of the 19th century, except for the countries that continued to use [[blackletter]] typefaces such as [[Fraktur]]. When blackletter type fell out of general use in the mid-20th century, even those countries dropped the long s.{{citation needed|date=September 2014}}
* The treatment of the Greek [[iota subscript]] with upper-case letters is complicated.
* Unlike most languages that use Latin-script and link the dotless upper-case "[[I]]" with the dotted lower-case "i", [[Turkish language|Turkish]], [[Tatar language|Tatar]] (including [[Crimean Tatar language|Crimean Tatar]]) as well as [[Azeri language#North Azerbaijani|some forms of Azeri]] have both a [[İ|dotted]] and [[dotless I]], each in both upper and lower case. Each of the two pairs ("<big>İ/i</big>" and "<big>I/ı</big>") represents a distinctive [[phoneme]].
* In some languages, specific digraphs may be regarded as single letters, and in [[Dutch language|Dutch]], the digraph "[[IJ (digraph)|IJ/ij]]" is even capitalised with both components written in uppercase (for example, "IJsland" rather than "Ijsland").<ref name="Taaladvies" /> In other languages, such as [[Welsh language|Welsh]] and [[Hungarian language|Hungarian]], various digraphs are regarded as single letters for collation purposes, but the second component of the digraph will still be written in lower case even if the first component is capitalised. Similarly, in [[South Slavic languages]] whose orthography is coordinated between the Cyrillic and Latin scripts, the Latin digraphs "[[Lj (letter)|ǈ/ǉ]]", "[[Nj (digraph)|ǋ/ǌ]]" and "[[Dž (digraph)|ǅ/ǆ]]" are each regarded as a single letter (like their Cyrillic equivalents "[[Lje|Љ/љ]]", "[[Nje|Њ/њ]]" and "[[Dzhe|Џ/џ]]", respectively), but only in all-caps style should both components be in upper case (e.g. ǈiǉan–ǇIǇAN, ǋoǌa–ǊOǊA, ǅiǆa–ǄIǄA).{{citation needed|date=September 2014}} [[Unicode]] designates a [[Digraph (orthography)#In Unicode|single character]] for each case variant (i.e., upper case, title case and lower case) of the three digraphs.<ref>{{cite web | url = https://www.unicode.org/charts/PDF/U0180.pdf | title = Latin Extended-B | at = U+01C4, U+01C5, U+01C6, U+01C7, U+01C8, U+01C9, U+01CA, U+01CB, U+01CC | publisher = Unicode | access-date = 5 February 2017 }}</ref>
* Some English surnames such as fforbes are traditionally spelt with a digraph instead of a capital letter (at least for ff).
* In the [[Hawaiian language|Hawaiian]] orthography, the [[ʻOkina|{{okina}}okina]] is a [[phonemic]] symbol that visually resembles a left single [[quotation mark]]. Representing the [[glottal stop]], the {{okina}}okina can be characterised as either a letter<ref>{{cite web | url = http://www.blondvoyage.com/single-post/2015/08/12/Why-I-Spell-it-Hawai%E2%80%98i-and-not-Hawaii-and-Why-You-Should-Too | title = Why I Spell it Hawai'i and not Hawaii, and Why You Should, Too | website = Blond Voyage | access-date = 6 August 2017 }}</ref> or a [[diacritic]].<ref>{{cite web | url = https://www.hawaii.edu/site/info/diacritics.php | title = Hawaiian Language Online | website = The University of Hawai‘i | access-date = 6 August 2017 }}</ref> As a unicase letter, the {{okina}}okina is unaffected by capitalisation; it is the following letter that is capitalised instead.

===Related features===
Similar orthographic and graphostylistic conventions are used for emphasis or following language-specific or other rules, including:
* [[Font]] effects such as [[italic type]] or [[oblique type]], [[boldface]], and choice of [[serif]] vs. [[sans-serif]].
* In [[mathematical notation]] lower-case and upper-case letters have generally different meanings, and other meanings can be implied by the use of other [[typeface]]s, such as [[boldface]], [[fraktur]], [[script typeface]], and [[blackboard bold]].
* Some letters of the [[Arabic alphabet|Arabic]] and [[Hebrew alphabet]]s and some [[Hangul consonant and vowel tables|jamo]] of the Korean [[hangul]] have different forms depending on placement within a word, but these rules are strict and the different forms cannot be used for emphasis.
**In the Arabic and Arabic-based alphabets, letters in a word are connected, except for several that cannot connect to the following letter. Letters may have distinct forms depending on whether they are initial (connected only to the following letter), medial (connected to both neighboring letters), final (connected only to the preceding letter), or isolated (connected to neither a preceding nor a following letter).
**In the Hebrew alphabet, five letters have a distinct form (see [[Final form]]) that is used when they are word-final.
* In [[Georgian alphabet|Georgian]], some authors use isolated letters from the ancient [[Asomtavruli]] alphabet within a text otherwise written in the modern [[Georgian alphabet#Mkhedruli|Mkhedruli]] in a fashion that is reminiscent of the usage of upper-case letters in the Latin, Greek, and Cyrillic alphabets.
* In the [[Japanese writing system]], an author has the option of switching between [[kanji]], [[hiragana]], [[katakana]], and [[rōmaji]]. In particular, every hiragana character has an equivalent katakana character, and vice versa. Romanised Japanese sometimes uses lowercase letters to represent words that would be written in hiragana, and uppercase letters to represent words that would be written in katakana. Some kana characters are written in smaller type when they modify or combine with the preceding sign (''[[yōon]]'') or the following sign (''[[sokuon]]'').

==Stylistic or specialised usage==
{{Globalize|section|Anglophone|2name=[[English-speaking world|the English-speaking world]]|date=September 2013}}[[File:Headline.png|thumb|182px|Alternating all-caps and headline styles at the start of a ''[[The New York Times|New York Times]]'' report published in November 1919. (The event reported is [[Arthur Eddington]]'s [[Experimentum crucis|test]] of [[Albert Einstein|Einstein]]'s [[General relativity|theory of general relativity]].)]]

In English, a variety of case styles are used in various circumstances:

; {{anchor|Sentence case|Sentence Case|Sentence-case|Sentencecase}}Sentence case
: "[[The quick brown fox jumps over the lazy dog]]"<br /> A mixed-case style in which the first word of the sentence is capitalised, as well as proper nouns and other words as required by a more specific rule. This is generally equivalent to the baseline universal standard of formal English orthography.
: In [[computer programming]], the initial capital is easier to automate than the other rules. For example, on English-language [[Wikipedia]], the first character in [[Wikipedia:Article titles|page titles]] is capitalised by default. Because the other rules are more complex, [[substring]]s for [[concatenation]] into sentences are commonly written in "mid-sentence case", applying all the rules of sentence case except the initial capital.
; {{anchor|Title case|Title Case|Title-case|Titlecase|Capital case|Capital Case|Capital-case|Capitalcase|Initial caps|Initial Caps|Initial-caps|Initialcaps}}[[Title case]] (capital case, headline style)
: "The Quick Brown Fox Jumps over the Lazy Dog"<br /> A mixed-case style with all words capitalised, except for certain subsets (particularly [[Article (grammar)|articles]] and short [[preposition]]s and [[Conjunction (grammar)|conjunctions]]) defined by rules that are not universally standardised. The standardisation is only at the level of house styles and individual [[style manual]]s. {{crossreference|printworthy=y|(See further explanation below at {{section link||Headings and publication titles}}.)}}
; {{anchor|Start case|Start Case|Start-case|Startcase|Initial caps|Initial Caps|Initial-caps|Initialcaps}} Start case (First letter of each word capitalized)
: "The Quick Brown Fox Jumps Over The Lazy Dog"<br /> ''Start case,'' ''initial caps'' or ''proper case'' is a simplified variant of title case. In [[text processing]], start case usually involves the capitalisation of all words irrespective of their [[part of speech]].
; {{anchor|All caps|All-caps|All Caps|All capitals|All Capitals|All-capitals|Uppercase|Upper-case|Upper case|Upper Case|All uppercase|All Uppercase|All-uppercase|All upper-case|All upper case}}[[All caps]] (all uppercase)
: "THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG"<br /> A unicase style with capital letters only. This can be used in headings and special situations, such as for typographical emphasis in text made on a typewriter. With the advent of the [[Internet]], the all-caps style is more often used for emphasis; however, it is considered poor [[netiquette]] by some to type in all capitals, and said to be tantamount to shouting.<ref name="RFC1855">RFC 1855 "Netiquette Guidelines"</ref> Long spans of Latin-alphabet text in all upper-case are more difficult to read because of the absence of the [[Ascender (typography)|ascenders]] and [[descender]]s found in lower-case letters, which aids recognition and legibility. In some cultures it is common to write family names in all caps to distinguish them from the given names, especially in identity documents such as passports. Certain musicians—such as [[Marina Diamandis|Marina]] and [[Finneas O'Connell|Finneas]], who are both known mononymously, and some bands such as [[Haim (band)|Haim]] and [[Kiss (band)|Kiss]]—have their names stylised in all caps. Additionally, it is common for bands with vowelless names (a process colourfully known as "[[disemvoweling]]") to use all caps, with prominent examples including [[Strfkr|STRFKR]], [[Mstrkrft|MSTRKRFT]], [[Pwr Bttm|PWR BTTM]], [[Sbtrkt|SBTRKT]], [[Hotel Mira|JPNSGRLS]] (now known as Hotel Mira), [[Blk Jks|BLK JKS]], [[MNDR]], and [[Dwntwn|DWNTWN]].
; {{anchor|Small caps|Small-caps|Small Caps|Small capitals|Small Capitals|Small-capitals}}[[Small caps]]
: "{{smallcaps|The quick brown fox jumps over the lazy dog}}"<br />Similar in form to capital letters but roughly the size of a lower-case "x", small caps can be used instead of lower-case letters and combined with regular caps in a mixed-case fashion. This is a feature of certain fonts, such as [[Copperplate Gothic]]. According to various typographical traditions, the height of small caps can be equal to or slightly larger than the [[x-height]] of the typeface (the smaller variant is sometimes called ''petite caps'' and may also be mixed with the larger variant).<ref>{{cite web | url = https://www.microsoft.com/typography/otspec/features_pt.htm#pcap | title = Registered features – definitions and implementations | website = OpenType Layout tag registry | at = Tag:'pcap', Tag: 'smcp' | publisher = Microsoft | access-date = 24 March 2017 }}</ref> Small caps can be used for acronyms, names, mathematical entities, computer commands in printed text, business or personal printed stationery letterheads, and other situations where a given phrase needs to be distinguished from the main text.
; {{anchor|Lower case|Lower Case|Lower-case|All lowercase|All-lowercase|All Lowercase|All lower-case|All lower case}}All lowercase
:"the quick brown fox jumps over the lazy dog"
:A unicase style with no capital letters. This is sometimes used for artistic effect, such as in poetry. Also commonly seen in computer languages, and in informal electronic communications such as [[SMS language]] and [[instant messaging]] (avoiding the [[shift key]], to type more quickly). Examples in music are relatively common. For example, several of [[Taylor Swift]]'s albums, including ''[[Reputation (album)|reputation]]'', ''[[Folklore (Taylor Swift album)|folklore]]'', and ''[[evermore]]'', were all stylised in lowercase. Bands such as [[Weezer]] and [[Silverchair]] were also stylised in lowercase for multiple albums during their respective careers, with the former consistently using lowercase in their logo since their [[Weezer (Blue Album)|first studio album]]. [[Billie Eilish]]'s debut studio album—''[[When We All Fall Asleep, Where Do We Go?]]''—has all of its tracks stylised in lowercase. Some people, such as author [[bell hooks]], write their names in all lowercase. Fully lowercase stylisation has been linked to the "disavowal of hierarchy", and on the Internet, frequently serves as "shorthand for authenticity and vulnerability".<ref>{{Cite web |last=Grady |first=Kitty |date=August 28, 2020 |title=The Rise of the 'Lowercase Girl' |url=https://www.vice.com/en/article/internet-lowercase-spelling-taylor-swift-charli-xcx/ |url-status=live |archive-url=https://ghostarchive.org/archive/GsTPc |archive-date=December 2, 2024 |access-date=December 2, 2024 |website=[[Vice Media|Vice]]}}</ref>
{| style="margin:0 auto 1.5em;font-size:95%;background:white;text-align:center;"
|+ style="text-align:left;font-size:110%;font-weight:bold;"| A comparison of various case styles (from most to least capitals used)
|- style="text-align:left;border-bottom:1px solid #aaa;"
| ''Case style''
|colspan="8"| ''Example''
|style="padding-left:1.0em;"| ''Description''

|- style="background:#d0d0d0;"
|style="background:white;text-align:left;"| All-caps
| &nbsp;THE&nbsp; || &nbsp;VITAMINS&nbsp; || &nbsp;ARE&nbsp; || &nbsp;IN&nbsp; || &nbsp;MY&nbsp; || &nbsp;FRESH&nbsp; || &nbsp;CALIFORNIA&nbsp; || &nbsp;RAISINS&nbsp;
|style="background:white;padding-left:1.0em;text-align:left;"| All letters uppercase

|- style="background:#e0e0e0;"
|style="background:white;text-align:left;"| Start case
| The || Vitamins || Are || In || My || Fresh || California || Raisins
|style="background:white;padding-left:1.0em;text-align:left;"| All words capitalised regardless of [[Part of speech|function]]

|- style="background:#e0e0e0;"
|style="background:white;text-align:left;"| Title case
| The || Vitamins || Are ||style="background:#f0f0f0;"| in || My || Fresh || California || Raisins
|style="background:white;padding-left:1.0em;text-align:left;"| The first word and all other words capitalised except for [[Article (grammar)|articles]] and short [[preposition]]s and [[Grammatical conjunction|conjunctions]]

|- style="background:#e0e0e0;"
|style="background:white;text-align:left;padding-right:1.0em;"| German, and Bavarian-style sentence case
| The || Vitamins ||style="background:#f0f0f0;"| are ||style="background:#f0f0f0;"| in ||style="background:#f0f0f0;"| my ||style="background:#f0f0f0;"| fresh || California || Raisins
|style="background:white;padding-left:1.0em;text-align:left;"| The first word and all [[noun]]s capitalised

|- style="background:#f0f0f0;"
|style="background:white;text-align:left;"| Sentence case
|style="background:#e0e0e0;"| The || vitamins || are || in || my || fresh ||style="background:#e0e0e0;"| California || raisins
|style="background:white;padding-left:1.0em;text-align:left;"| The first word, [[proper noun]]s and some specified words capitalised

|- style="background:#f0f0f0;"
|style="background:white;text-align:left;"| Mid-sentence case
| the || vitamins || are || in || my || fresh ||style="background:#e0e0e0;"| California || raisins
|style="background:white;padding-left:1.0em;text-align:left;"| As above but excepting special treatment of the first word

|- style="background:#f0f0f0;"
|style="background:white;text-align:left;"| All-lowercase
| the || vitamins || are || in || my || fresh || {{not a typo|california}} || raisins
|style="background:white;padding-left:1.0em;text-align:left;"| All letters lowercase (unconventional in English prose)
|}

=== Headings and publication titles ===
In English-language publications, various conventions are used for the capitalisation of words in [[Title (publishing)|publication title]]s and [[headline]]s, including chapter and section headings. The rules differ substantially between individual house styles.

The convention followed by many British [[publisher]]s (including scientific publishers like ''[[Nature (journal)|Nature]]'' and ''[[New Scientist]]'', magazines like ''[[The Economist]]'', and newspapers like ''[[The Guardian]]'' and ''[[The Times]]'') and many U.S. newspapers is sentence-style capitalisation in headlines, i.e. capitalisation follows the same rules that apply for sentences. This convention is usually called ''sentence case''. It may also be applied to publication titles, especially in bibliographic references and library catalogues. An example of a global publisher whose English-language house style prescribes sentence-case titles and headings is the [[International Organization for Standardization]] (ISO).{{Citation needed|date=June 2024}}

For publication titles it is, however, a common typographic practice among both British<ref name="Guardian" /> and U.S. publishers to capitalise significant words (and in the United States, this is often applied to headings, too). This family of typographic conventions is usually called ''[[title case]]''. For example, R.&nbsp;M. Ritter's ''Oxford Manual of Style'' (2002) suggests capitalising "the first word and all nouns, pronouns, adjectives, verbs and adverbs, but generally not articles, conjunctions and short prepositions".<ref name="Ritter 2002" /> This is an old form of [[Emphasis (typography)|emphasis]], similar to the more modern practice of using a larger or boldface font for titles. The rules which prescribe which words to capitalise are not based on any grammatically inherent correct&ndash;incorrect distinction and are not universally standardised; they differ between style guides, although most style guides tend to follow a few strong conventions, as follows:
* Most styles capitalise all words except for short [[Closed class|closed-class]] words (certain [[Part of speech|parts of speech]], namely, articles, prepositions, and conjunctions); but the first word (always) and last word (in many styles) are also capitalised, regardless of their part of speech. Many styles capitalise longer prepositions such as "between" and "throughout", but not shorter ones such as "for" and "with".<ref name="Berdine" /> Typically, a preposition is considered short if it has up to three or four letters.
* A few styles capitalise all words in title case (the so-called ''start case''), which has the advantage of being easy to implement and hard to get "wrong" (that is, "not edited to style"). Because of this rule's simplicity, software [[#Case folding|case-folding]] routines can handle 95% or more of the editing, especially if they are programmed for desired exceptions (such as "FBI" rather than "Fbi").
* As for whether hyphenated words are capitalised not only at the beginning but also after the hyphen, there is no universal standard; variation occurs [[Linguistic description|in the wild]] and among house styles (e.g., "The Letter-''C''ase Rule in My Book"; "Short-''t''erm Follow-''u''p Care for Burns"). Traditional copyediting makes a distinction between ''temporary compounds'' (such as many [[Nonce word|nonce]] [novel instance] [[compound modifier]]s), in which every part of the hyphenated word is capitalised (e.g. "How This Particular Author Chose to Style His ''A''utumn-''A''pple-''P''icking Heading"), and ''permanent compounds'', which are terms that, although compound and hyphenated, are so well established that dictionaries enter them as [[headword]]s (e.g., "Short-''t''erm Follow-''u''p Care for Burns").

Title case is widely used in many English-language publications, especially in the United States. However, its conventions are sometimes not followed strictly{{Snd}}especially in informal writing.

In creative typography, such as music record covers and other artistic material, all styles are commonly encountered, including all-lowercase letters and special case styles, such as [[studly caps]] (see below). For example, in the [[wordmark]]s of video games it is not uncommon to use stylised upper-case letters at the beginning and end of a title, with the intermediate letters in small caps or lower case (e.g., [[Arcania: Gothic 4|{{smallcaps|ArcaniA}}]], [[ARMA: Armed Assault|{{smallcaps|ArmA}}]], and [[DmC: Devil May Cry|DmC]]).

=== Multi-word proper nouns ===
Single-word [[proper nouns]] are capitalised in formal written English, unless the name is intentionally stylised to break this rule (such as [[e e cummings]], [[bell hooks]], [[eden ahbez]], and [[danah boyd]]).

Multi-word proper nouns include names of organisations, publications, and people. Often the rules for "title case" (described in the previous section) are applied to these names, so that non-initial articles, conjunctions, and short prepositions are lowercase, and all other words are uppercase. For example, the short preposition "of" and the article "the" are lowercase in "Steering Committee of the Finance Department". Usually only capitalised words are used to form an [[acronym]] variant of the name, though there is some variation in this.

With [[personal names]], this practice can vary (sometimes all words are capitalised, regardless of length or function), but is not limited to English names. Examples include the English names [[Tamar of Georgia]] and [[Catherine the Great]], "[[van (Dutch)|van]]" and "der" in [[Dutch name]]s, "[[von]]" and "zu" in [[German name|German]], "de", "los", and "y" in [[Spanish naming customs|Spanish names]], "de" or "d'" in [[French name]]s, and "ibn" in [[Arabic name]]s.

Some surname prefixes also affect the capitalisation of the following internal letter or word, for example "Mac" in [[Surname#Celtic compound names|Celtic names]] and "Al" in Arabic names.

{{Anchor|Special case styles|Special Case Styles|Special-case-styles}}

===Unit symbols and prefixes in the metric system===
[[File:SI base units.svg|thumb|Of the seven [[SI base unit|SI base-unit]] symbols, "A" ([[ampere]] for [[electric current]]) and "K" ([[kelvin]] for [[temperature]]), both named after people, are always written in upper case, whereas "s" ([[second]] for [[time]]), "m" ([[metre]] for [[length]]), "kg" ([[kilogram]] for [[mass]]), "cd" ([[candela]] for [[luminous intensity]]), and "mol" ([[Mole (unit)|mole]] for [[amount of substance]]) are written in lower case.]]

In the [[International System of Units]] (SI), a letter usually has different meanings in upper and lower case when used as a unit symbol. Generally, unit symbols are written in lower case, but if the name of the unit is derived from a proper noun, the first letter of the symbol is capitalised. Nevertheless, the ''name'' of the unit, if spelled out, is always considered a common noun and written accordingly in lower case.<ref name="SI brochure" /> For example:

* 1&nbsp;s (one&nbsp;[[second]]) when used for the [[SI base unit|base unit]] of [[time]].
* 1&nbsp;S (one&nbsp;[[siemens (unit)|siemens]]) when used for the unit of [[electric conductance]] and [[admittance]] (named after [[Werner von Siemens]]).
* 1&nbsp;Sv (one&nbsp;[[sievert]]), used for the unit of [[ionising radiation]] dose (named after [[Rolf Maximilian Sievert]]).

For the purpose of clarity, the symbol for [[litre]] can optionally be written in upper case even though the name is not derived from a proper noun.<ref name="SI brochure" /> For example, "one&nbsp;litre" may be written as:

* {{not a typo|1 l}}, the original form, for typefaces in which "digit one" {{angbr|1}}, "lower-case ell" {{angbr|l}}, and "upper-case i" {{angbr|I}} look different.
* 1&nbsp;L, an alternative form, for typefaces in which these characters are difficult to distinguish, or the typeface the reader will be using is unknown. A "[[ℓ|script l]]" in various typefaces (e.g.: 1&nbsp;<span style="font-family: cursive;">l</span>) has traditionally been used in some countries to prevent confusion; however, the separate [[Unicode character]] which represents this, {{Unichar|2113|SCRIPT SMALL L}}, is deprecated by the [[International System of Units|SI]].<ref>{{cite web|url=https://www.unicode.org/charts/beta/nameslist/n_2100.html|title=Letterlike symbols|work=Charts (Beta)|publisher=[[Unicode Consortium]]|access-date=28 July 2017}}</ref> Another solution sometimes seen in [[Web typography]] is to use a serif font for "lower-case ell" in otherwise sans-serif material (1&nbsp;<span style="font-family: serif;">l</span>).

The letter case of a prefix symbol is determined independently of the unit symbol to which it is attached. Lower case is used for all submultiple prefix symbols and the small multiple prefix symbols up to "k" (for [[kilo-|kilo]], meaning 10<sup>3</sup> = 1000 multiplier), whereas upper case is used for larger multipliers:<ref name="SI brochure" />

* 1&nbsp;mW, [[watt|milliwatt]], a small measure of [[power (physics)|power]] ("m" for [[milli-|milli]], meaning 10<sup>−3</sup> = 1/1000 multiplier).
* 1&nbsp;MW, megawatt, a large measure of power ("M" for [[mega-|mega]], meaning 10<sup>6</sup> = 1&nbsp;000&nbsp;000 multiplier).
* 1&nbsp;mS, [[millisiemens]], a small measure of electric conductance.
* 1&nbsp;MS, megasiemens, a large measure of electric conductance.
* 1&nbsp;mm, millimetre, a small measure of [[length]].
* 1&nbsp;Mm, megametre, a large measure of length.

===Use within programming languages===
{{See also|Naming convention (programming)#Multiple-word identifiers}}
Some case styles are not used in standard English, but are common in [[computer programming]], product [[brand]]ing, or other specialised fields.

The usage derives from how programming languages are [[parsing|parsed]], programmatically. They generally separate their syntactic tokens by simple [[Whitespace character|whitespace]], including [[space character]]s, [[tab key|tabs]], and [[newline]]s. When the tokens, such as function and variable names start to multiply in complex [[software development]], and there is still a need to keep the [[source code]] human-readable, [[Naming convention (programming)|Naming conventions]] make this possible. So for example, a function dealing with matrix multiplication might formally be called:

* {{code|SGEMM(*)}}, with the asterisk standing in for an equally inscrutable list of 13 parameters (in [[Basic Linear Algebra Subprograms|BLAS]]),
* {{code|MultiplyMatrixByMatrix(Matrix x, Matrix y)}}, in some hypothetical higher level [[manifest typing|manifestly typed]] language, broadly following the syntax of [[C++]] or [[Java (programming language)|Java]],
* {{code|multiply-matrix-by-matrix(x, y)}} in something derived from [[LISP]], or perhaps
* {{code|(multiply (x y))}} in the [[Common Lisp Object System|CLOS]], or some newer derivative language supporting [[type inference]] and [[multiple dispatch]].

In each case, the capitalisation or lack thereof supports a different function. In the first, [[FORTRAN]] compatibility requires case-insensitive naming and short function names. The second supports easily discernible function and argument names and types, within the context of an imperative, strongly typed language. The third supports the macro facilities of LISP, and its tendency to view programs and data minimalistically, and as interchangeable. The fourth idiom needs much less [[syntactic sugar]] overall, because much of the semantics are implied, but because of its brevity and so lack of the need for capitalization or multipart words at all, might also make the code too abstract and [[homonymy|overloaded]] for the common programmer to understand.

Understandably then, such coding conventions are [[programming style|highly subjective]], and can lead to rather opinionated debate, such as in the case of [[editor war]]s, or those about [[indent style]]. Capitalisation is no exception.

====Camel case====
{{main|Camel case}}
{{blockquote|"theQuickBrownFoxJumpsOverTheLazyDog" or "TheQuickBrownFoxJumpsOverTheLazyDog"}}
Spaces and [[punctuation]] are removed and the first letter of each word is capitalised. If this includes the first letter of the first word (CamelCase, "[[PowerPoint]]", "TheQuick...", etc.), the case is sometimes called '''upper camel case''' (or, illustratively, '''CamelCase'''), '''Pascal case''' in reference to the [[Pascal (programming language)|Pascal programming language]]<ref>{{cite web|url=https://docs.microsoft.com/en-us/archive/blogs/brada/history-around-pascal-casing-and-camel-casing|title=History around Pascal Casing and Camel Casing|date=3 February 2004 }}</ref> or '''bumpy case'''.

When the first letter of the first word is lowercase ("[[iPod]]", "[[eBay]]", "theQuickBrownFox..."), the case is usually known as '''lower camel case''' or '''dromedary case''' (illustratively: '''dromedaryCase'''). This format has become popular in the branding of [[information technology]] products and services, with an initial "i" meaning "[[Internet]]" or "intelligent",{{Citation needed|date=August 2022}} as in [[iPod]], or an initial "e" meaning "electronic", as in [[email]] (electronic mail) or [[e-commerce]] (electronic commerce).

====Snake case====
{{main|Snake case}}
{{blockquote|"the_quick_brown_fox_jumps_over_the_lazy_dog"}}
Punctuation is removed and spaces are replaced by single [[underscore]]s. Normally the letters share the same case (e.g. "UPPER_CASE_EMBEDDED_UNDERSCORE" or "lower_case_embedded_underscore") but the case can be mixed, as in [[OCaml]] variant constructors (e.g. "Upper_then_lowercase").<ref>{{Cite web|url=http://caml.inria.fr/resources/doc/guides/guidelines.en.html|title=Caml programming guidelines|website=caml.inria.fr|language=en|access-date=2017-03-31}}</ref> The style may also be called ''pothole case'', especially in [[Python (programming language)|Python]] programming, in which this convention is often used for naming variables. Illustratively, it may be rendered ''snake_case'', ''pothole_case'', etc.. When all-upper-case, it may be referred to as ''screaming snake case'' (or ''SCREAMING_SNAKE_CASE'') or ''hazard case''.<ref name="Ruby" />

====Kebab case====
{{blockquote|"the-quick-brown-fox-jumps-over-the-lazy-dog"}}
Similar to snake case, above, except [[hyphen]]s rather than underscores are used to replace spaces. It is also known as '''spinal case''', '''param case''', '''Lisp case''' in reference to the [[Lisp (programming language)|Lisp programming language]], or '''dash case''' (or illustratively as '''kebab-case''', looking similar to the skewer that sticks through a [[kebab]]). If every word is capitalised, the style is known as '''train case''' (''TRAIN-CASE'').<ref>{{cite web |date=15 January 2023 |title=Programming naming conventions |website=Pluralsight |url=https://www.pluralsight.com/resources/blog/software-development/programming-naming-conventions-explained#train-case |at=11. Train case |access-date=16 November 2024 }}</ref>

In [[CSS]], all property names and most keyword values are primarily formatted in kebab case.

==== Middot case ====
{{blockquote|"the·quick·brown·fox·jumps·over·the·lazy·dog"}}
Similar to kebab case, above, except it uses [[interpunct]] rather than underscores to replace spaces. Its use is possible in many programming languages supporting Unicode identifiers, as unlike the hyphen it generally doesn't conflict with a reserved use for denoting an operator, albeit exceptions such as [[Julia (programming language)|Julia]] exist.<ref>{{Cite web |title=Variables · The Julia Language |url=https://docs.julialang.org/en/v1/manual/variables/ |access-date=2025-03-28 |website=docs.julialang.org |language=en}}</ref> Its lack of visibility in most standard keyboard layouts certainly contribute to its infrequent employ, though most modern input facility allow to reach it rather easily.<ref>{{Cite web |title=What is the meaning of an interpunct (·) in C? |url=https://stackoverflow.com/questions/15396199/what-is-the-meaning-of-an-interpunct-in-c |access-date=2025-03-28 |website=Stack Overflow |language=en}}</ref>

=== Studly caps ===
{{blockquote|"tHeqUicKBrOWnFoXJUmpsoVeRThElAzydOG"}}
Studly caps are an arbitrary mixing of the cases with no [[Semantics|semantic]] or [[Syntax|syntactic]] significance to the use of the capitals. Sometimes only [[vowel]]s are upper case, at other times upper and lower case are alternated, but often it is simply random. The name comes from the sarcastic or ironic implication that it was used in an attempt by the writer to convey their own [[coolness]] ([[wikt:studly|studliness]]).{{citation needed|date=February 2023}} It is also used to mock the violation of standard English case conventions by marketers in the naming of computer software packages, even when there is no technical requirement to do so{{snd}}e.g., [[Sun Microsystems]]' naming of a windowing system [[NeWS]]. Illustrative naming of the style is, naturally, random: ''stUdlY cAps'', ''StUdLy CaPs'', etc..

=={{Anchor | Case folding}}Case folding and case conversion==
In the [[character set]]s developed for [[computing]], each upper- and lower-case letter is encoded as a separate character. In order to enable case folding and case conversion, the [[software]] needs to link together the two characters representing the case variants of a letter. (Some old character-encoding systems, such as the [[Baudot code]], are restricted to one set of letters, usually represented by the upper-case variants.)

[[Case sensitivity|Case-insensitive]] operations can be said to fold case, from the idea of folding the character code table so that upper- and lower-case letters coincide. The conversion of letter case in a [[String (computer science)|string]] is common practice in computer applications, for instance to make case-insensitive comparisons. Many high-level programming languages provide simple methods for case conversion, at least for the [[ASCII]] character set.

Whether or not the case variants are treated as equivalent to each other varies depending on the computer system and context. For example, user [[password]]s are generally case sensitive in order to allow more diversity and make them more difficult to break. In contrast, case is often ignored in [[keyword search]]es in order to ignore insignificant variations in keyword capitalisation both in queries and queried material.

===Unicode case folding and script identification===
[[Unicode]] defines case folding through the three case-mapping properties of each [[Character (computing)|character]]: upper case, lower case, and title case (in this context, "title case" relates to [[Typographic ligature|ligature]]s and [[Digraph (orthography)|digraph]]s encoded as mixed-case [[Digraph (orthography)#In Unicode|single characters]], in which the first component is in upper case and the second component in lower case).<ref>{{cite web | url = http://unicode.org/faq/casemap_charprop.html#4 | title = Character Properties, Case Mappings & Names FAQ | publisher = Unicode | access-date = 19 February 2017}}</ref> These properties relate all characters in scripts with differing cases to the other case variants of the character.

As briefly discussed in [[Unicode]] Technical Note #26,<ref name="Unicode" /> "In terms of implementation issues, any attempt at a unification of Latin, Greek, and Cyrillic would wreak havoc [and] make casing operations an unholy mess, in effect making all casing operations context sensitive […]". In other words, while the shapes of letters like '''A''', '''B''', '''E''', '''H''', '''K''', '''M''', '''O''', '''P''', '''T''', '''X''', '''Y''' and so on are shared between the Latin, Greek, and Cyrillic alphabets (and small differences in their canonical forms may be considered to be of a merely [[Typography|typographical]] nature), it would still be problematic for a multilingual [[character set]] or a [[font]] to provide only a ''single'' [[code point]] for, say, uppercase letter '''B''', as this would make it quite difficult for a wordprocessor to change that single uppercase letter to one of the three different choices for the lower-case letter, the Latin '''b''' (U+0062), Greek '''β''' (U+03B2) or Cyrillic '''в''' (U+0432). Therefore, the corresponding Latin, Greek and Cyrillic upper-case letters (U+0042, U+0392 and U+0412, respectively) are also encoded as separate characters, despite their appearance being identical. Without letter case, a "unified European alphabet"{{spaced ndash}}such as '''ABБCГDΔΕЄЗFΦGHIИJ'''...'''Z''', with an appropriate subset for each language{{spaced ndash}}is feasible; but considering letter case, it becomes very clear that these alphabets are rather distinct sets of symbols.

===Methods in word processing===
Most modern [[word processor]]s provide automated case conversion with a simple click or keystroke. For example, in Microsoft Office Word, there is a dialog box for toggling the selected text through UPPERCASE, then lowercase, then Title Case (actually start caps; exception words must be lowercased individually). The keystroke {{keypress|shift|F3}} does the same.

===Methods in programming===
In some forms of [[BASIC]] there are two methods for case conversion:

<syntaxhighlight lang="qbasic">
UpperA$ = UCASE$("a")
LowerA$ = LCASE$("A")
</syntaxhighlight>

[[C (programming language)|C]] and [[C++]], as well as any C-like language that conforms to its [[C standard library|standard library]], provide these functions in the file [[ctype.h]]:

<syntaxhighlight lang="c">
char upperA = toupper('a');
char lowerA = tolower('A');
</syntaxhighlight>

Case conversion is different with different [[character sets]]. In [[ASCII]] or [[EBCDIC]], case can be converted in the following way, in C:
<syntaxhighlight lang="c">
int toupper(int c) { return islower(c) ? c – 'a' + 'A' : c; }
int tolower(int c) { return isupper(c) ? c – 'A' + 'a' : c; }
</syntaxhighlight>
This only works because the letters of upper and lower cases are spaced out equally. In ASCII they are consecutive, whereas with EBCDIC they are not; nonetheless the upper-case letters are arranged in the same pattern and with the same gaps as are the lower-case letters, so the technique still works.

Some computer programming languages offer facilities for converting text to a form in which all words are capitalised. [[Visual Basic]] calls this "proper case"; [[Python (programming language)|Python]] calls it "title case". This differs from usual [[Capitalization#Title case|title casing]] conventions, such as the English convention in which minor words are not capitalised.

==History==
{{See also|Initial}}
{{Multiple image
| direction = vertical
| width = 250
| image1 = Arch.of.Titus-Inscription.jpg
| caption1 = Latin majuscule inscription on the [[Arch of Titus]] (82 CE)
| image2 = I littera in manuscripto.jpg
| caption2 = Papyrus fragment with old Roman cursive script from the reign of [[Claudius]] (41–54 CE)
| image3 = Codex Ebnerianus Prolog J 1, 5b-10.JPG
| caption3 = Example of Greek minuscule text [[Codex Ebnerianus]] ({{circa}} 1100 CE)
}}
{{Multiple image
| direction = vertical
| width = 250
| image1 = A Typesetters Sorting Case.jpg
| caption1 = Combined case with capital letters above small letters
| image2 = 2 job cases.jpg
| caption2 = Late 19th-century mixed cases
| image3 = PrintMus 026.jpg
| caption3 = Demonstrating the use of a [[composing stick]] in front of divided upper and lower type cases at the [[International Printing Museum]] in Carson, California, United States, North America
}}
Originally [[alphabet]]s were written entirely in majuscule letters, spaced between well-defined upper and lower bounds. When written quickly with a [[pen]], these tended to turn into rounder and much simpler forms. It is from these that the first minuscule hands developed, the [[half-uncial]]s and cursive minuscule, which no longer stayed bound between a pair of lines.<ref name="Harris 2003" /> These in turn formed the foundations for the [[Carolingian minuscule]] script, developed by [[Alcuin]] for use in the court of [[Charlemagne]], which quickly spread across Europe. The advantage of the minuscule over majuscule was improved, faster readability.{{citation needed|date=December 2014}}

In [[Latin]], [[Papyrus|papyri]] from [[Herculaneum]] dating before 79 CE (when it was destroyed) have been found that have been written in old [[Roman cursive]], where the early forms of minuscule letters "d", "h" and "r", for example, can already be recognised. According to papyrologist [[Knut Kleve]], "The theory, then, that the lower-case letters have been developed from the fifth century [[uncial]]s and the ninth century Carolingian minuscules seems to be wrong."<ref name="Kleve 1994" /> Both majuscule and minuscule letters existed, but the difference between the two variants was initially stylistic rather than orthographic and the writing system was still basically unicameral: a given handwritten document could use either one style or the other but these were not mixed. European languages, except for [[Ancient Greek]] and Latin, did not make the case distinction before about 1300.{{citation needed|date=February 2014}}

The timeline of writing in Western Europe can be divided into four eras:{{citation needed|date=October 2017}}
*Greek majuscule (9th–3rd&nbsp;century BCE) in contrast to the Greek [[uncial script]] (3rd century BCE&nbsp;– 12th&nbsp;century CE) and the later [[Greek minuscule]]
*[[Roman square capitals|Roman majuscule]] (7th&nbsp;century BCE&nbsp;– 4th&nbsp;century CE) in contrast to the Roman uncial (4th–8th&nbsp;century CE), [[Roman half uncial]], and minuscule
*[[Carolingian]] majuscule (4th–8th&nbsp;century CE) in contrast to the [[Carolingian minuscule]] (around 780&nbsp;– 12th&nbsp;century)
*[[Blackletter|Gothic]] majuscule (13th and 14th&nbsp;century), in contrast to the early Gothic (end of 11th to 13th&nbsp;century), Gothic (14th&nbsp;century), and late Gothic (16t&nbsp; century) minuscules.

Traditionally, certain letters were rendered differently according to a set of rules. In particular, those letters that began sentences or nouns were made larger and often written in a distinct script. There was no fixed capitalisation system until the early 18th century. The [[English language]] eventually dropped the rule for nouns, while the German language keeps it.

Similar developments have taken place in other alphabets. The lower-case script for the [[Greek alphabet]] has its origins in the 7th century and acquired its quadrilinear form (that is, characterised by ascenders and descenders)<ref>{{Cite web|url=https://gilbertredman.com/medievalmanuscripts/paleography/roman-writing-systems/|title=Roman Writing Systems – Medieval Manuscripts|language=en-US|access-date=2019-07-03}}</ref> in the 8th century. Over time, uncial letter forms were increasingly mixed into the script. The earliest dated Greek lower-case text is the [[Uspenski Gospels]] (MS 461) in the year 835.<ref>The earliest known biblical manuscript is a palimpsest of Isajah in Syriac, written in 459/460. [[Bruce M. Metzger]] & [[Bart D. Ehrman]], ''The Text of the New Testament'' ([[Oxford University Press]]: 2005), p. 92.</ref> The modern practice of capitalising the first letter of every sentence seems to be imported (and is rarely used when printing Ancient Greek materials even today).{{citation needed|date=October 2017}}

[[File:Evolution of minuscule.svg|thumb|center|700px
|Simplified relationship between various scripts leading to the development of modern lower case of standard Latin alphabet and that of the modern variants [[Fraktur (script)|Fraktur]] (used in Germany [[Antiqua–Fraktur dispute|until 1940s]]) and [[Gaelic type|Gaelic]] (used in Ireland). Several scripts coexisted such as [[half-uncial]] and [[uncial]], which derive from [[Roman cursive]] and [[Greek uncial]], and [[Visigothic script|Visigothic]], [[Merovingian script|Merovingian (Luxeuil variant here)]] and [[Beneventan script|Beneventan]]. The [[Carolingian script]] was the basis for [[blackletter]] and [[humanist minuscule]]. What is commonly called "Gothic writing" is technically called blackletter (here [[Textualis|textualis quadrata]]) and is completely unrelated to Visigothic script.

The letter j is i with a [[Swash (typography)|flourish]], u and v are the same letter in early scripts and were used depending on their position in insular half-uncial and caroline minuscule and later scripts, w is a ligature of vv, in insular the [[rune]] [[wynn]] is used as a w (three other runes in use were the [[Thorn (letter)|thorn]] (þ), ʻféʼ (ᚠ) as an abbreviation for cattle/goods and maðr (ᛘ) for man).

The letters y and z were very rarely used, in particular þ was written identically to y so y was dotted to avoid confusion, the dot was adopted for i only after late-caroline (protogothic), in beneventan script the [[Scribal abbreviation|macron abbreviation]] featured a dot above.

Lost variants such as [[r rotunda]], ligatures and [[Scribal abbreviation|scribal abbreviation marks]] are omitted; [[long s]] is shown when no terminal s (the only variant used today) is preserved from a given script.

[[Humanist sans-serif|Humanist script]] was the basis for Venetian [[Typeface|types]] which changed little until today, such as [[Times Roman|Times New Roman]] ([[Serif|a serifed typeface]]).
]]

===Type cases===
The individual type blocks used in hand [[typesetting]] are stored in shallow wooden or metal drawers known as "[[type case]]s". Each is subdivided into a number of compartments ("boxes") for the storage of different individual letters.{{citation needed|date=October 2017}}

The ''Oxford Universal Dictionary on Historical Advanced Proportional Principles'' (reprinted 1952) indicates that ''case'' in this sense (referring to the box or frame used by a compositor in the printing trade) was first used in English in 1588. Originally one large case was used for each typeface, then "divided cases", pairs of cases for majuscules and minuscules, were introduced in the region of today's Belgium by 1563, England by 1588, and France before 1723.

The terms ''upper'' and ''lower'' case originate from this division. By convention, when the two cases were taken out of the storage rack and placed on a rack on the [[Compositor (typesetting)|compositor]]'s desk, the case containing the capitals and small capitals stood at a steeper angle at the back of the desk, with the case for the small letters, punctuation, and spaces being more easily reached at a shallower angle below it to the front of the desk, hence upper and lower case.<ref name="Bolton 1997" />

Though pairs of cases were used in English-speaking countries and many European countries in the seventeenth century, in Germany and Scandinavia the single case continued in use.<ref name="Bolton 1997" />

Various patterns of cases are available, often with the compartments for lower-case letters varying in size according to the frequency of use of letters, so that the commonest letters are grouped together in larger boxes at the centre of the case.<ref name="Bolton 1997" /> The compositor takes the letter blocks from the compartments and places them in a [[composing stick]], working from left to right and placing the letters upside down with the nick to the top, then sets the assembled type in a [[Galley proof|galley]].<ref name="Bolton 1997" />

==See also==
{{Div col|colwidth=15em}}
* [[All caps]]
* [[Alternating caps]]
* [[Camel case]]
* [[Capitalization]]
** [[Capitalization in English]]
* [[Initial]], or drop cap
* [[Grammatical case]]
* [[Punctuation]]
* [[Roman cursive]]
* [[Roman square capitals]]
* [[Shift key]]
* [[Small caps]]
* [[Text figures]]
* [[Unicase]]
{{Div col end}}

== Notes ==
{{NoteFoot}}

== References ==
{{reflist | refs =
<ref name="AHD 2000">{{cite book |title=[[The American Heritage Dictionary of the English Language]] |edition=4th |publisher=Houghton Mifflin |year=2000 |location=Boston and New York |isbn=978-0-395-82517-4}}</ref>
<ref name="Berdine">{{cite news |url=http://adminsecret.monster.com/training/articles/358-what-to-capitalize-in-a-title |title=What to Capitalize in a Title |author=Currin Berdine |website=AdminSecret |access-date=23 February 2014}}</ref>
<ref name="Bloomberg">{{cite web |url=http://www.jhsph.edu/news/style_manual/h.html |title=The School's Manual of Style |publisher=Johns Hopkins, Bloomberg School of Public Health |access-date=9 November 2018}}</ref>
<ref name="Bolton 1997">{{cite web |url=http://members.aol.com/typecases/index.htm |title=Type Cases |author=David Bolton |publisher=The Alembic Press |year=1997 |access-date=23 April 2007 |archive-url=https://web.archive.org/web/20070716153655/http://members.aol.com/typecases/index.htm |archive-date=16 July 2007}}</ref>
<ref name="Guardian">{{cite web |url=https://www.theguardian.com/guardian-observer-style-guide-t |title=The Guardian and Observer Style Guide |website=[[TheGuardian.com]] |access-date=10 June 2014}}</ref>
<ref name="Harris 2003">{{cite book |author=David Harris |title=The Calligrapher's Bible |publisher=Barron's |year=2003 |location=Hauppauge, NY |isbn=0-7641-5615-2}}</ref>
<ref name="Kleve 1994">{{cite book |author=Knut Kleve |author-link=Knut Kleve |chapter=The Latin Papyri in Herculaneum |title=Proceedings of the 20th International Congress of Papyrologists, Copenhagen, 23–29 August 1992 |publisher=Museum Tusculanum Press |year=1994 |location=Copenhagen}}</ref>
<ref name="Lewis 1890">{{cite book |author=Charlton T. Lewis |chapter=Minusculus |chapter-url=https://www.perseus.tufts.edu/cgi-bin/ptext?doc=Perseus%3Atext%3A1999.04.0060%3Aentry%3D%239936 |title=An Elementary Latin Dictionary |year=1890 |location=New York, Cincinnati, and Chicago |publisher=American Book Company }}</ref>
<ref name="Ritter 2002">{{cite book |title=Oxford Manual of Style |editor=R. M. Ritter |publisher=[[Oxford University Press]] |year=2002}}</ref>
<ref name="Ruby">{{cite web |url=https://github.com/bbatsov/ruby-style-guide#naming |title=Ruby Style Guide |website=[[GitHub]] |access-date=11 November 2013}}</ref>
<ref name="SI brochure">{{cite web |url=http://www.bipm.org/utils/common/pdf/si_brochure_8_en.pdf |title=The International System of Units |author=Bureau International des Poids et Mesures |publisher=Organisation Intergouvernementale de la Convention du Mètre |pages=121, 130–131 |year=2006 |access-date=12 January 2014}}</ref>
<ref name="Taaladvies">{{cite web |url=http://taaladvies.net/taal/advies/vraag/1188/ |title=Ijsland / IJsland |publisher=Taalunie |access-date=9 March 2014}}</ref>
<ref name="Unicode">{{cite web |url=https://www.unicode.org/notes/tn26/ |title=Unicode Technical Note #26: On the Encoding of Latin, Greek, Cyrillic, and Han |access-date=23 April 2007}}</ref>
|30em}}

== Further reading ==
{{Commons category|Capital letters}}
* {{cite book |last=Hamilton |first=Frederick W. |date=1918 |title=Capitals: A Primer of Information About Capitalization with Some Practical Typographic Hints as to the Use of Capitals |url=https://www.gutenberg.org/ebooks/20374 |via=[[Project Gutenberg]]}}

== External links ==
{{Wiktionary|capital letter|lowercase|minuscule|Appendix:Capital letter}}

#  [https://www.upperlowercase.com/ Upper Lower Case Online Converter] is a tool for converting text among upper-, lower-, proper and sentence case formats.

{{Typography terms}}

[[Category:Alphabets]]
[[Category:Capitalization]]
[[Category:Orthography]]
[[Category:Typography]]
[[Category:Articles with example C code]]