TextEdit is a simple, open source word processor and text editor, first featured in NeXT's NEXTSTEP and OPENSTEP. It is now distributed with Mac OS X since Apple Inc.'s acquisition of NeXT, and available as a GNUstep application for other Unix-compatible operating systems such as Linux. It is powered by Apple Advanced Typography and has many advanced typography features.

TextEdit replaced the text editor of previous Macintosh operating systems, SimpleText. TextEdit reads and writes documents in Rich Text Format, Rich Text Format Directory, plain text, and HTML formats, and can open (but not save) old SimpleText files. It also has access to the operating system's built-in spell-checking service. The version included in Mac OS X v10.3 added the ability to read and write documents in Word format, and the version in Mac OS X v10.4 the ability to read and write Word XML documents. The version included in Mac OS X v10.5 includes read and write support for Office Open XML and OpenDocument Text. The version included in Mac OS X v10.6 added automatic spelling correction, support for data detectors, and text transformations. The version included in Mac OS X v10.7 includes Versioning of files, and Autosave similar to iOS.