A text editor is a piece of computer software for editing plain text. It is distinguished from a word processor in that it does not manage document formatting or other features commonly used in desktop publishing. Such programs are often bundled with an operating system or software development package, and are commonly used for editing operating system and application configuration files and programming language source code.
Some text editors are small and simple, while others offer a broad and complex range of functionality. For example, Unix and Unix-like operating systems have the vi editor (or a variant), but many also include the Emacs editor to edit text as well Microsoft Windows systems use the very simple Notepad program, though many people (especially programmers) use a more complete program like TextPad. For the Mac Operating System there is the native SimpleText, which was replaced, or supplemented by WorldText, and also the HTML editor BBEdit.
Some editors include special features and extra functions, as instance,