Editing BASIC (section)

== Explosive growth: the home computer era ==
{{See also|List of computers with on-board BASIC}}
[[File:CommodoreBasic.png|thumb|[[Commodore BASIC]] v2.0 on the [[Commodore 64]] ]]
[[File:Msxbasic.png|thumb|[[MSX BASIC]] version 3.0]]
[[File:Pn-pravez-class-5.jpg|thumb|right|"Train Basic every day!"—reads a poster (bottom center) in a Russian school ({{circa|1985–86}})]]

The introduction of the first [[microcomputer]]s in the mid-1970s was the start of explosive growth for BASIC. It had the advantage that it was fairly well known to the young designers and computer hobbyists who took an interest in microcomputers, many of whom had seen BASIC on minis or mainframes. Despite [[Edsger W. Dijkstra|Dijkstra]]'s famous judgment in 1975, "It is practically impossible to teach good programming to students that have had a prior exposure to BASIC: as potential programmers they are mentally mutilated beyond hope of regeneration",<ref>{{Cite book|chapter-url=https://www.cs.utexas.edu/users/EWD/ewd04xx/EWD498.PDF |archive-url=https://ghostarchive.org/archive/20221009/https://www.cs.utexas.edu/users/EWD/ewd04xx/EWD498.PDF |archive-date=2022-10-09 |url-status=live|chapter=How do we tell truths that might hurt |title=Selected Writings on Computing: A Personal Perspective |first=Edsger W. |last=Dijkstra|date=June 18, 1975 |publication-date=1982 |publisher=[[Springer-Verlag]]|isbn=978-0387906522|oclc=693424350 |pages=[https://archive.org/details/selectedwritings0000dijk/page/129 129–131] |url=https://archive.org/details/selectedwritings0000dijk/page/129}}</ref> BASIC was one of the few languages that was both high-level enough to be usable by those without training and small enough to fit into the microcomputers of the day, making it the ''de facto'' standard programming language on early microcomputers.

The first [[Altair BASIC|microcomputer version]] of BASIC was co-written by [[Bill Gates]], [[Paul Allen]] and [[Monte Davidoff]] for their newly formed company, Micro-Soft.<ref>{{Cite web |last=Johnson |first=Phil |date=2015-01-21 |title=The source code behind Microsoft BASIC for 6502 comes to light |url=https://www.computerworld.com/article/2872659/the-source-code-behind-microsoft-basic-for-6502-comes-to-light.html |access-date=2022-10-24 |website=Computerworld |language=en}}</ref> This was released by MITS in [[punch tape]] format for the [[Altair 8800]] shortly after the machine itself,<ref>{{Cite web|title=We have a BASIC|publisher=[[New Mexico Museum of Natural History and Science]]|url=http://startup.nmnaturalhistory.org/gallery/story.php?ii=20&sid=4|access-date=April 18, 2007|archive-url=https://web.archive.org/web/20121130051115/http://startup.nmnaturalhistory.org/gallery/story.php?ii=20&sid=4|archive-date=November 30, 2012}}</ref> immediately cementing BASIC as the primary language of early microcomputers. Members of the [[Homebrew Computer Club]] began circulating copies of the program, causing Gates to write his [[Open Letter to Hobbyists]], complaining about this early example of [[software piracy]].

Partially in response to Gates's letter, and partially to make an even smaller BASIC that would run usefully on 4&nbsp;KB machines,{{efn|Microsoft BASIC left 780 bytes free for user program code and variable values on a 4K machine, and that was running a cut-down version lacking string variables and other functionality.}} [[Bob Albrecht]] urged [[Dennis Allison]] to write their own variation of the language. How to design and implement a stripped-down version of an [[interpreter (computing)|interpreter]] for the BASIC language was covered in articles by Allison in the first three quarterly issues of the ''[[People's Computer Company]]'' newsletter published in 1975 and implementations with source code published in ''[[Dr. Dobb's Journal of Tiny BASIC Calisthenics & Orthodontia: Running Light Without Overbyte]]''. This led to a wide variety of [[Tiny BASIC]]s with added features or other improvements, with versions from Tom Pittman and [[Li-Chen Wang]] becoming particularly well known.<ref>{{Cite web |url=http://www.ittybittycomputers.com/IttyBitty/iNotes.html#TinyBasic|title=you had to pay $5 up front to get it… |last=Pittman |first=Tom |website=www.ittybittycomputers.com |access-date=June 14, 2017}}</ref>

Micro-Soft, by this time [[Microsoft]], ported their interpreter for the [[MOS 6502]], which quickly become one of the most popular microprocessors of the 8-bit era. When new microcomputers began to appear, notably the "1977 trinity" of the [[TRS-80]], [[Commodore PET]] and [[Apple II]], they either included a version of the MS code, or quickly introduced new models with it. [[Ohio Scientific|Ohio Scientific's]] personal computers also joined this trend at that time. By 1978, MS BASIC was a ''de facto'' standard and practically every [[home computer]] of the 1980s included it in [[read-only memory|ROM]]. Upon boot, a BASIC interpreter in [[direct mode]] was presented.

[[Commodore Business Machines]] includes [[Commodore BASIC]], based on Microsoft BASIC. The Apple II and TRS-80 each have two versions of BASIC: a smaller introductory version with the initial releases of the machines and a Microsoft-based version introduced as interest in the platforms increased. As new companies entered the field, additional versions were added that subtly changed the BASIC family. The [[Atari 8-bit computers]] use the 8&nbsp;KB [[Atari BASIC]] which is not derived from Microsoft BASIC. [[Sinclair BASIC]] was introduced in 1980 with the Sinclair [[ZX80]], and was later extended for the Sinclair [[ZX81]] and the Sinclair [[ZX Spectrum]]. The [[BBC]] published [[BBC BASIC]], developed by [[Acorn Computers]], incorporates extra [[structured programming]] keywords and floating-point features.

As the popularity of BASIC grew in this period, computer magazines published complete source code in BASIC for video games, utilities, and other programs. Given BASIC's straightforward nature, it was a simple matter to [[Type-in program|type in the code]] from the magazine and execute the program. Different magazines were published featuring programs for specific computers, though some BASIC programs were considered universal and could be used in machines running any variant of BASIC (sometimes with minor adaptations). Many books of type-in programs were also available, and in particular, Ahl published versions of the original 101 BASIC games converted into the Microsoft dialect and published it from ''Creative Computing'' as ''[[BASIC Computer Games]]''. This book, and its sequels, provided hundreds of ready-to-go programs that could be easily converted to practically any BASIC-running platform.<ref name="basicgames" /><ref>{{Cite book|url=http://www.atariarchives.org/morebasicgames/|title=More basic computer games|last=Ahl|first=David H.|date=1979|publisher=Creative Computing Press|isbn=978-0894801372|oclc=839377789|location=Morristown|language=en}}</ref><ref>{{Cite book|url=http://www.atariarchives.org/bigcomputergames/|title=Big computer games|last=Ahl|first=David H.|date=1984|publisher=Creative Computing Press|isbn=978-0916688400|oclc=872675092|location=Morris Plains, N.J.|language=en}}</ref> The book reached the stores in 1978, just as the [[home computer]] market was starting off, and it became the first million-selling computer book. Later packages, such as Learn to Program BASIC would also have gaming as an introductory focus. On the business-focused [[CP/M]] computers which soon became widespread in small business environments, [[Microsoft BASIC]] ([[MBASIC]]) was one of the leading applications.<ref name="oldcomputer">{{Cite web|url=http://oldcomputers.net/osborne-1.html|title=Osborne 1|website=oldcomputers.net|access-date=June 14, 2017}}</ref>

In 1978, David Lien published the first edition of ''The BASIC Handbook: An Encyclopedia of the BASIC Computer Language'', documenting keywords across over 78 different computers. By 1981, the second edition documented keywords from over 250 different computers, showcasing the explosive growth of the microcomputer era.<ref>{{cite book |last1=Lien |first1=David |title=The BASIC Handbook |date=1981 |publisher=Compusoft Publishing |location=San Diego, CA |isbn=0-932760-00-7 |page=inside cover |edition=Second}}</ref>