Scroll Lock

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.

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

Pressing Ctrl+Scroll Lock performs the same function as pressing Ctrl+Break (Pause). This behavior is a remnant of the original IBM PC keyboards, which did not have a dedicated Break (Pause) key. Instead, they assigned the Pause function to Ctrl+Num Lock and the Break function to Ctrl+Scroll Lock.

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