Work on LISP spread from John McCarthy’s original M.I.T. project to other projects at M.I.T. and then to other institutions as people moved on and word about the capabilities of the language spread. John Allen brought a snapshot of the M.I.T.’s PDP-6 LISP to Stanford where it evolved into Stanford LISP 1.6 through the work of Allen, Lynn Quam, and Whitfield Diffie. It was rendered obsolete by MACLISP and Interlisp.