Editing MacOS version history (section)

=== Mac OS X 10.5 Leopard ===
[[Mac OS X Leopard]] was released on October 26, 2007. Apple called it "the largest update of Mac OS X". Leopard supports both [[PowerPC]]- and [[X86|Intel x86]]-based Macintosh computers; support for Macs with the G3 processor was dropped, and Macs with the G4 processor required a minimum clock rate of 867&nbsp;MHz and at least 512 MB of [[Random-access memory|RAM]] to be installed. The single DVD works for all supported Macs (including 64-bit machines). New features include a new look, an updated Finder, [[Time Machine (macOS)|Time Machine]], [[Spaces (software)|Spaces]], [[Boot Camp (software)|Boot Camp]] pre-installed,<ref name="bootcamp">
{{cite web
| url=https://www.apple.com/macosx/bootcamp/
| title=Apple&nbsp;– BootCamp
| year=2006
| access-date=June 5, 2006
| publisher=[[Apple Inc.|Apple]]
|archive-url = https://web.archive.org/web/20060602044022/http://www.apple.com/macosx/bootcamp/ |archive-date = June 2, 2006}}</ref> full support for [[64-bit]] applications (including graphical applications), new features in [[Mail (OS X)|Mail]] and [[iChat]], and a number of new security features.

Leopard, on the Intel platform, is the first [[Single UNIX Specification|Open Brand UNIX 03]] registered version of macOS. It was also the first [[Berkeley Software Distribution|BSD-based]] OS to receive UNIX 03 certification.<ref name="Leopard UNIX certification"/><ref>
{{cite web
| publisher=[[Apple Inc.|Apple]]
| title=Mac OS X Leopard&nbsp;– Technology&nbsp;– UNIX
| url=https://www.apple.com/server/macosx/technology/unix.html
| work=Leopard Technology Overview
| access-date=October 26, 2007
| quote=Leopard is now an Open Brand UNIX 03 Registered Product, conforming to the SUSv3 and POSIX 1003.1 specifications for the C API, Shell Utilities, and Threads.
| url-status=dead
| archive-url=https://web.archive.org/web/20110609032125/http://www.apple.com/server/macosx/technology/unix.html
| archive-date=June 9, 2011
}}</ref> Leopard dropped support for the [[Classic Environment]] and all Classic applications,<ref>{{cite web
| url=http://docs.info.apple.com/article.html?artnum=303137
| title=Do Classic applications work with Mac OS X 10.5 or Intel-based Macs?
| publisher=[[Apple Inc.|Apple]]
| work=Knowledge Base
| date=January 13, 2006
| access-date=October 25, 2007
| url-status=dead
| archive-url=https://web.archive.org/web/20071025084826/http://docs.info.apple.com/article.html?artnum=303137
| archive-date=October 25, 2007
}}</ref> and was the final version of Mac OS X to support the PowerPC architecture.