Emacs family editors derive from the design of Richard M. Stallman's Editing MACroS, a package of macros written in the TECO(Text Editor and COrrector) language that ran on the ITS (Incompatible Timesharing System) at MIT in the '70s. Emacs was subsequently implemented in the C language by James Gosling and by Stallman himself, and spawned a family of editors that shared the design philosophy.