- Mouse is an interpreted stack orientated language designed by Peter Grogono around 1975. It was designed to be a small but powerful language for microcomputers, similar to Forth, but much simpler. One obvious difference to Forth is that Mouse interprets a stream of characters most of which are only a single character and it relies more on variables rather than rearranging the stack as much. The version for CP/M on the Walnut Creek CD is quite small at only 2k.