Editing X86 (section)

===From 16-bit and 32-bit to 64-bit architecture===
The [[instruction set architecture]] has twice been extended to a larger [[Word (computer architecture)|word]] size. In 1985, Intel released the 32-bit 80386 (later known as i386) which gradually replaced the earlier 16-bit chips in computers (although typically not in [[embedded system]]s) during the following years; this extended programming model was originally referred to as ''the i386 architecture'' (like its first implementation) but Intel later dubbed it [[IA-32]] when introducing its (unrelated) [[IA-64]] architecture.

In 1999–2003, [[Advanced Micro Devices|AMD]] extended this 32-bit architecture to 64&nbsp;bits and referred to it as [[x86-64]] in early documents and later as [[AMD64]]. Intel soon adopted AMD's architectural extensions under the name IA-32e, later using the name EM64T and finally using Intel 64. [[Microsoft]] and [[Sun Microsystems]]/[[Oracle Corporation|Oracle]] also use term "x64", while many [[Linux distribution]]s, and the [[BSD]]s also use the "amd64" term. Microsoft Windows, for example, designates its 32-bit versions as "x86" and 64-bit versions as "x64", while installation files of 64-bit Windows versions are required to be placed into a directory called "AMD64".<ref>{{cite web|url=http://support.microsoft.com/kb/896334|title=Setup and installation considerations for Windows x64 Edition-based computers|access-date=September 14, 2014|archive-date=September 11, 2014|archive-url=https://web.archive.org/web/20140911011914/http://support.microsoft.com/kb/896334|url-status=live}}</ref>

In 2023, Intel proposed a major change to the architecture referred to as [[X86-64#X86S|X86S]] (formerly known as X86-S). The S in X86S stood for "simplification", which aimed to remove support for legacy execution modes and instructions. A processor implementing this proposal would start execution directly in [[long mode]] and would only support 64-bit operating systems. 32-bit code would only be supported for user applications running in ring 3, and would use the same simplified segmentation as long mode.<ref>{{Cite web |title=Envisioning a Simplified Intel Architecture |url=https://www.intel.com/content/www/us/en/developer/articles/technical/envisioning-future-simplified-architecture.html |website=Intel}}</ref><ref>{{Cite news |last=Larabel |first=Michael |date=2023-05-20 |title=Intel Publishes "X86-S" Specification For 64-bit Only Architecture |work=[[Phoronix]] |url=https://www.phoronix.com/news/Intel-X86-S-64-bit-Only |access-date=2023-05-20}}</ref> In December 2024 Intel cancelled this project.<ref>{{Cite web |title=toms hardware X86S |url=https://www.tomshardware.com/pc-components/cpus/intel-terminates-x86s-initiative-unilateral-quest-to-de-bloat-x86-instruction-set-comes-to-an-end}}</ref>