Space-cadet keyboard

The space-cadet keyboard is a keyboard used on MIT Lisp machines and designed by Tom Knight, which inspired several still-current jargon terms in the field of computer science and influenced the design of Emacs. It was inspired by the Knight keyboard (also developed by Tom Knight), which was developed for the Knight TV system, used with MIT's Incompatible Timesharing System.

The Symbolics-labeled version shown here was only used with the LM-2, which was Symbolics's repackaged version of the MIT CADR. Later Symbolics systems used a greatly simplified keyboard, the Symbolics keyboard, that retained only the basic layout and the more commonly used function and modifier keys from the space-cadet keyboard.

The space-cadet keyboard was equipped with seven modifier keys: four keys for bucky bits (Control, Meta, Super, and Hyper), and three shift keys, called ⇧ Shift, Top, and Front (which was labeled Greek on its top). Meta had been introduced on the earlier Knight keyboard, while Hyper and Super were introduced by this keyboard. Each group was in a row, thus allowing easy pressing of several modifier keys via chording; for example, Control+Meta+Hyper+Super could be pressed with the fingers of one hand, while pressing another key with the other hand.

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