Initially emacs was prototyped as a series of editor commands or macros for the late 1960s text editor TECO (Text Editor and COrrector). The acronymic name, Editor MACroS, reflects these beginnings, although there have been many humorous reinterpretations, including ESCAPE META ALT CONTROL SHIFT, Emacs Makes All Computing Simple, and the unkind translation Eight Megabytes And Constantly Swapping.
Since then, emacs has grown and evolved through more than 20 major revisions to the mainstream GNU version alone. The emacs editor, coded in C, contains a complete Lisp interpreter and fully supports the X Window System and mouse interaction. The original TECO macros are long gone, and emacs is a work still very much in progress. The ...