Editing Software versioning (section)

== Software examples ==

===Python===
The [[Python Software Foundation]] has published PEP 440 – Version Identification and Dependency Specification,<ref name="PEP440">{{cite web|url=https://www.python.org/dev/peps/pep-0440/|title=PEP 440 – Version Identification and Dependency Specification}}</ref> outlining their own flexible scheme, that defines an epoch segment, a release segment, pre-release and post-release segments and a development release segment.

===TeX===
[[TeX]] has an [[idiosyncratic]] version numbering system, an unusual feature invented by its developer [[Donald Knuth]]. Since version 3.1, updates have been indicated by adding an extra digit at the end, so that the version number [[asymptotically]] approaches the number [[pi|{{pi}}]], so 3.14 effectively means 3.2 in semantic versioning. (This is a form of [[Unary numeral system|unary numbering]]; the version number is the number of digits.) Since 2021, the version number has been 3.141592653 (3.9). This is a reflection of TeX being very stable, and only minor updates are anticipated. TeX developer Donald Knuth has stated that the ''"absolutely final change (to be made after [his] death)"'' will be to change the version number to {{pi}}, at which point all remaining bugs will become permanent features.<ref name="tb30knut">{{cite journal |last1=Knuth |first1=Donald E. |date=December 1990 |title=The Future of TeX and Metafont |url=https://tug.org/TUGboat/tb11-4/tb30knut.pdf |journal=TUGboat |volume=11 |issue=4 |pages=489 |access-date=7 September 2023}}</ref>

In a similar way, the version number of [[Metafont]] asymptotically approaches [[E (mathematical constant)|Euler's number, {{mvar|e}}]].<ref name="tb30knut" /> As of February 2021, the version number is 2.71828182 (2.8). Metafont was also devised by Donald Knuth as a companion to his TeX typesetting system.

===Apple===
During the era of the [[classic Mac OS]], minor version numbers rarely went beyond ".1". When they did, they usually jumped straight to ".5", suggesting the release was "more significant".{{efn|The complete sequence of classic Mac OS versions (not including patches) is: 1.0, 1.1, 2.0, 2.1, 3.0, 3.2 (skipping 3.1), 4.0, 4.1, 5.0, 5.1, 6.0, 7.0, 7.1, 7.5, 7.6, 8.0, 8.1, 8.5 (jumped), 8.6, 9.0, 9.1, 9.2.}} Thus, "8.5" was marketed as its own release, representing "Mac OS 8 and a half", and 8.6 effectively meant "8.5.1".

[[Mac OS X history|Mac OS X]] departed from this trend, in large part because "X" (the Roman numeral for 10) was in the name of the product. As a result, all versions of OS X began with the number 10. The first major release of OS X was given the version number 10.0, but the next major release was not 11.0. Instead, it was numbered 10.1, followed by 10.2, 10.3, and so on for each subsequent major release. Thus the 11th major version of OS X was labeled "10.10". Even though the "X" was dropped from the name as of [[MacOS Sierra|macOS 10.12]], this numbering scheme continued through macOS 10.15. Under the "X"-based versioning scheme, the third number (instead of the second) denoted a minor release, and additional updates below this level, as well as updates to a given major version of OS X coming after the release of a new major version, were titled Supplemental Updates.<ref>{{Cite news|url=https://www.macrumors.com/2018/02/19/apple-releases-macos-10-13-3-supplemental-update/|title=Apple Releases macOS 10.13.3 Supplemental Update With Telugu Crash Fix|access-date=March 26, 2018|language=en}}</ref>

The Roman numeral X was concurrently leveraged for marketing purposes across multiple product lines. Both [[QuickTime]] and [[Final Cut Pro]] jumped from version 7 directly to version 10, QuickTime X and Final Cut Pro X. Like Mac OS X itself, the products were not upgrades to previous versions, but brand-new programs. As with OS X, major releases for these programs incremented the second digit and minor releases were denoted using a third digit. The "X" was dropped from Final Cut's name with the release of macOS 11.0 (see below), and QuickTime's branding became moot when the framework was deprecated in favor of AVFoundation in 2011 (the program for playing QuickTime video was only named QuickTime Player from the start).

Apple's next macOS release, provisionally numbered 10.16,<ref name="Gallagher, AppleInsider 2020.06.22">{{cite news|last1=Gallagher|first1=William|date=June 22, 2020|title=Apple turns macOS up to 11 – or to 10.16|publisher=AppleInsider|url=https://appleinsider.com/articles/20/06/22/apple-turns-macos-up-to-11---or-to-1016}}</ref> was officially announced as [[macOS Big Sur|macOS 11]] at WWDC in June 2020, and released in November 2020.<ref>{{cite news|last1=Heater |first1=Brian|title=Apple unveils macOS 11.0 Big Sur|url=https://techcrunch.com/2020/06/22/apple-unveils-macos-10-16-big-sur/|website=TechCrunch|access-date=June 22, 2020|archive-url=https://web.archive.org/web/20200622183548/https://techcrunch.com/2020/06/22/apple-unveils-macos-10-16-big-sur/|archive-date=June 22, 2020|url-status=live}}</ref> The following macOS version, [[macOS Monterey]], was released in October 2021 and bumped its major version number to 12.<ref name="BGR, 2021.10.12">{{cite news|last1=De Looper|first1=Christian|date=Oct 12, 2021|title=Apple macOS Monterey: Everything we know so far|publisher=BGR|archive-url=https://web.archive.org/web/20211010180620/https://bgr.com/tech/apple-macos-monterey-news/|archive-date=October 10, 2021|url=https://bgr.com/tech/apple-macos-monterey-news/}}</ref>

===Microsoft Windows===
The [[Microsoft Windows]] operating system was first labelled with standard version numbers for [[Windows 1.0]] through [[Windows 3.1x|Windows 3.11]]. After this Microsoft excluded the version number from the product name. For [[Windows 95]] (version 4.0), [[Windows 98]] (4.10) and [[Windows 2000]] (5.0), year of the release was included in the product title. After Windows 2000, Microsoft created the [[Windows Server]] family which continued the year-based style with a difference: For minor releases, Microsoft suffixed "R2" to the title, e.g., [[Windows Server 2008 R2]] (version 6.1). This style had remained consistent to this date. The client versions of Windows however did not adopt a consistent style. First, they received names with arbitrary alphanumeric suffixes as with [[Windows Me]] (4.90), [[Windows XP]] (5.1), and [[Windows Vista]] (6.0). Then, once again Microsoft adopted incremental numbers in the title, but this time, they were not versioning numbers; the version numbers of [[Windows 7]], [[Windows 8]] and [[Windows 8.1]] are respectively 6.1, 6.2 and 6.3. In [[Windows 10]], the version number leaped to 10.0<ref>{{cite web|title=Announcing Windows 10|work=Blogging Windows |date=September 30, 2014 |url=http://blogs.windows.com/bloggingwindows/2014/09/30/announcing-windows-10/}}</ref> and [[Windows 10 version history|subsequent updates to the OS]] only incremented build number and update build revision (UBR) number.

The successor of Windows 10, [[Windows 11]], was released on October 5, 2021. Despite being named "11", the new Windows release didn't bump its major version number to 11. Instead, it stayed at the same version number of 10.0, used by Windows 10.<ref>{{cite web|title=Windows 11: A new era for the PC begins today|url=https://blogs.windows.com/windowsexperience/2021/10/04/windows-11-a-new-era-for-the-pc-begins-today/|date=Oct 4, 2021|website=Windows Blogs}}</ref>