Editing Unicode (section)

=== Operating systems ===
Unicode has become the dominant scheme for the internal processing and storage of text. Although a great deal of text is still stored in legacy encodings, Unicode is used almost exclusively for building new information processing systems. Early adopters tended to use [[Universal Coded Character Set|UCS-2]] (the fixed-length two-byte obsolete precursor to UTF-16) and later moved to [[UTF-16]] (the variable-length current standard), as this was the least disruptive way to add support for non-BMP characters. The best known such system is [[Windows NT]] (and its descendants, [[Windows 2000|2000]], [[Windows XP|XP]], [[Windows Vista|Vista]], [[Windows 7|7]], [[Windows 8|8]], [[Windows 10|10]], and [[Windows 11|11]]), which uses UTF-16 as the sole internal character encoding. The [[Java virtual machine|Java]] and [[.NET Framework|.NET]] bytecode environments, [[macOS]], and [[KDE]] also use it for internal representation. Partial support for Unicode can be installed on [[Windows 9x]] through the Microsoft Layer for Unicode.

[[UTF-8]] (originally developed for [[Plan 9 from Bell Labs|Plan 9]])<ref>{{Cite web |last=Pike |first=Rob |author-link=Rob Pike |date=30 April 2003 |title=UTF-8 history |url=https://www.cl.cam.ac.uk/~mgk25/ucs/utf-8-history.txt}}</ref> has become the main storage encoding on most [[Unix-like]] operating systems (though others are also used by some libraries) because it is a relatively easy replacement for traditional [[extended ASCII]] character sets. UTF-8 is also the most common Unicode encoding used in [[HTML]] documents on the [[World Wide Web]].

Multilingual text-rendering engines which use Unicode include [[Uniscribe]] and [[DirectWrite]] for Microsoft Windows, [[ATSUI]] and [[Core Text]] for macOS, and [[Pango]] for [[GTK+]] and the [[GNOME]] desktop.