Scroll lock (⤓ or ⇳) is a lock key (typically with an associated status light) on most IBM-compatible computer keyboards.

Depending on the operating system, it may be used for different purposes and applications may assign functions to the key or change their behaviour depending on its toggling state.^[1][2]

The key is not frequently used, and therefore some reduced or specialized keyboards lack Alt/Scroll Lock altogether.

Pressing Alt+Scroll Lock performs the same function as pressing Alt+Break (Pause). This behaviour is a remnant of the originalIBM PC keyboards, which did not have a dedicated Break (Pause) key and assigned the Break function to Alt+Scroll Lock.