Cut, copy, and paste Apple mapped the functionalities to key combinations consisting of the Command key (a special modifier key) held down while typing the letters X (for cut), C (for copy), and V (for paste), choosing a handful of keyboard shortcuts to control basic editing operations. The keys involved all cluster together at the left end of the bottom row of the standard QWERTY keyboard, and each key is combined with a special modifier key to perform the desired operation: The IBM Common User Access (CUA) standard also uses combinations of the Insert, Del, Shift and Control keys. Early versions of Windows used
Fn key Fn key in Mac OS X. Fn is a modifier key, and works like other modifiers keys, such as Ctrl, Shift, Alt and AltGr. For a standard modifier key, the microcontroller inside the keyboard sends a scancode for the modifier itself, which is then interpreted by the operating system and combined with other simultaneous key-presses. The Fn key is a form of meta-modifier key, in that it causes the operating system to see altered scancodes when other keys on the keyboard are pressed. This allows the keyboard to directly emulate a full-sized keyboard, so the operating system can use standard