Command key keyboard of the NeXT Computer that key was marked in green. The menus were not marked with a symbol denoting the command key. Besides being used as a modifier key for keyboard shortcuts it was also used to alter the function of some keys. toggles alpha lock, sends Enter and toggles Mute. The functions were printed in green on the front side of the modified keys. This was also done on the Z, X, C and V keys (Undo, Cut, Copy and Paste). On the NeXT ADB keyboard, the Command keys were replaced by keys labeled and the Command key
Computer keyboard were compromised to allow for the mechanical limitations of the typewriter. As the letter-keys were attached to levers that needed to move freely, inventor Christopher Sholes developed the QWERTY layout to reduce the likelihood of jamming. With the advent of computers, lever jams are no longer an issue, but nevertheless, QWERTY layouts were adopted for electronic keyboards because they were widely used. Alternative layouts such as the Dvorak Simplified Keyboard are not in widespread use. The QWERTZ layout is widely used in Germany and much of Central Europe. The main difference between it and QWERTY is that Y and Z