Text Services Framework
A standalone Language Bar inWindows XP, with language selection menu open
Developer	Microsoft
Operating system	Microsoft Windows
Platform	IA-32,x86-64,Itanium,ARM64
Predecessor	Input Method Manager (IMM32)
Type	Software framework
Website	docs.microsoft.com/en-us/windows/win32/tsf/text-services-framework

TheText Services Framework (TSF) is aCOMframework andAPI in theMicrosoft Windowsoperating system that supports advanced text input and text processing. It was introduced inWindows XP. TheLanguage Bar is the coreuser interface for Text Services Framework.

The Text Services Framework is designed to offer advanced language andword processing features to applications. It supports features such as multilingual support, keyboard drivers,handwriting recognition,speech recognition, as well asspell checking and other text andnatural language processing functions. It is also downloadable for older Windows operating systems.^[1]

The Language Bar enables text services to add UI elements to the toolbar and enables these elements when an application has focus. From the Language Bar, users can select the input language, and control keyboard input, handwriting recognition and speech recognition.

The language bar also provides a direct means to switch between installed languages, even when a non-TSF-enabled application has focus.

Starting withWindows XP Tablet PC Edition 2005 andWindows Vista, theRichEdit control supports the Text Services Framework.Windows Speech Recognition in Windows Vista is also implemented using the Text Services Framework.

Language bar tools – From left: Language selection menu, spell checking, keyboard layout selection menu, speech recognition, tools, handwriting recognition and drawing pad

• TSF is extensible.Independent software vendors can write their own text processing feature for TSF.
• TSF-enabled applications can receive text input from any text service that supports TSF without having to be aware of any details of the text source.^[2] Services built using TSF are globally available to any application.
• TSF enables a text service to storemetadata with a document, a piece of text, or an object within the document. For example, a speech input text service can store sound information associated with a block of text.^[3]
• TSF enables text services to provide accurate and complete text conversion, with continuous access to the document buffer. Text services using TSF can avoid separating their functionality into modes for input and modes for editing. This input architecture enables the buffered and accumulating text stream to change dynamically, thereby enabling more efficient keyboard input and text editing.^[3]
• TSF isdevice-independent and enables text services for multiple input devices includingkeyboard,electronic pen or stylus, andmicrophone.^[3]

ctfmon (ctfmon.exe) is a process used to activate the Alternative User Input Text Input Processor (TIP) and also the MicrosoftLanguage Bar. Ctfmon is also a component ofWindows XP,Windows Vista andWindows 7 which enables advanced user input services in applications (pen and ink, speech etc.).^[4]ctfmon.exe inWindows XP has supersededinternat.exe (meansinternational) inWindows 95,Windows NT 4.0,Windows 98 andWindows 2000.

CTF meansCommon Text Framework (codenameCicero, according to the leaked Windows XP source code^[5]) andUS 7490296  patent text.

In August 2019,Google Project Zero discovered and publicly exposed a critical security vulnerability in CTF that dated back to its first release in Windows XP. The vulnerability, known as CVE-2019-1162, allows privilege escalation and security boundary traversal. Microsoft patched this vulnerability in August 2019.^[6][7][8]

• Text Services Framework documentation on MSDN
• Text Services Framework blog
• How to use the language bar in Windows XP
• The Language Bar in Windows XP
• Language Bar Overview: Windows Vista Help

• Input methods
• Windows components
• Natural language and computing
• Internationalization and localization

• Articles with short description
• Short description matches Wikidata