Caps lock

Caps Lock is a button on a computer keyboard that, when pressed, causes all letters to be generated in capitals until deactivated. It is located in the position of a similar Shift lock key (and sometimes a Ctrl key) found in some other keyboard layouts. It is usually a toggle key: each press reverses its action. Exactly what Caps Lock does depends on the operating system and driver, and the keyboard layout implemented. On non-IBM PC-compatible computers it may also depend on the keyboard hardware.