Editing Windows API (section)

=={{anchor|Win16|Win32|Win32c|Win32s|Win64|WinCE}}Major versions==
Each version of Microsoft Windows contains a version of Windows API, and almost every new version of Microsoft Windows has introduced additions and changes to the Windows API.<ref name="win32faq-history">The Iseran Project (1996–2001). ''[https://web.archive.org/web/20020802081510/http://www.iseran.com/Win32/FAQ/history.html History of the Windows API.]'' Retrieved October 7, 2005.</ref> 

The name, Windows API, refers to essentially the same capability in each version of Windows, but there is another name for this capability that is based on major architectural aspects of the Windows version that contains it. When there was only one version, it was simply called Windows API. Then, when the first major update was made, Microsoft gave it the name Win32 and gave the first version the name Win16. The term Windows API refers to both versions and all subsequently developed major versions.<ref name="msdn-overview2">[[Microsoft Developer Network]] (July 2005). ''[http://msdn.microsoft.com/library/default.asp?url=/library/en-us/winprog/winprog/overview_of_the_windows_api.asp Overview of the Windows API.]'' Retrieved August 28, 2005.</ref>

* '''Win16''' is in the [[16-bit computing|16-bit]] versions of Windows. The functions reside mainly in core files of the OS: ''kernel.exe'' (or ''krnl286.exe'' or ''krnl386.exe''), ''user.exe'' and ''gdi.exe''. Despite the [[file extension]] of <samp>exe</samp>, such a file is accessed as a DLL.
* '''Win32''' is in the [[32-bit computing|32-bit]] versions of Windows (NT, 95, and later). The functions are implemented in system DLL files including [[kernel32.dll]], [[Windows USER|user32.dll]], and [[gdi32.dll]]. Win32 was introduced with [[Windows NT]]. In [[Windows 95]], it was initially referred to as Win32c, with ''c'' meaning ''compatibility''. This term was later abandoned by Microsoft in favor of Win32.
* '''[[Win32s]]''' is an extension for the [[Windows 3.1x#Windows 3.1|Windows 3.1x]] family of Microsoft Windows that implemented a [[subset]] of the Win32 API for these systems. The "s" stands for "subset".
* '''Win64''' is the version in the [[64-bit computing|64-bit]] [[Windows NT#Supported platforms|platforms]] of the [[Architecture of the Windows NT operating system line|Windows architecture]] ({{as of|2021|lc=on}}, [[x86-64]] and [[AArch64]]).{{efn|Nomenclature of released 64-bit versions includes [[Windows XP Professional x64 Edition]] and x64 Editions of Windows Server 2003, Windows Vista and Windows Server 2008 on the x86-64 (AMD64) platform, and [[Windows 2000]] Server Limited Edition, [[Windows XP 64-bit Edition]], Windows Advanced Server 2003 for [[Itanium]] and Windows 2008 Advanced Server for [[Itanium]] on the [[IA-64]] platform.}}<ref name="XPx64">{{cite web |url=http://www.microsoft.com/windowsxp/64bit/ |title=Windows XP Professional x64 Edition home page |publisher=Microsoft|archive-url=https://web.archive.org/web/20060111151707/http://www.microsoft.com/windowsxp/64bit/default.mspx|archive-date=2006-01-11|url-status=dead}}</ref><ref name="2003x64">{{cite web |url=http://www.microsoft.com/servers/64bit/ |title=Microsoft 64-bit Computing Overview |publisher=Microsoft |archive-url=https://web.archive.org/web/20090112225501/http://www.microsoft.com/servers/64bit/overview.mspx |archive-date=2009-01-12 |url-status = dead}}</ref> Both 32-bit and 64-bit versions of an application can be compiled from one [[codebase]], although some older API functions have been deprecated, and some of the API functions that were deprecated in Win32 were removed. All memory [[pointer (computer programming)|pointers]] are 64-bit by default (the [[LLP64]] model), so porting Win32-compatible source code includes updating for 64-bit [[pointer arithmetic]].<ref name="64bitMigration">{{cite web |url=http://msdn.microsoft.com/en-us/library/aa384198(VS.85).aspx |title=MSDN: Getting Ready for 64-bit Windows |date=August 19, 2020 |publisher=Microsoft}}</ref>
* '''WinCE''' is the version in the [[Windows CE]] operating system.