*** Welcome to piglix ***

Lock key


LOCK is a function that locks part of a keyboard keys into a distinct mode of operation, depending on the lock settings selected.

Most keyboards have three different types of lock functions:

The lock keys are scattered around the keyboard. Most styles of keyboards have three LEDs indicating which locks are enabled, in the upper right corner above the numpad. Some ergonomic keyboards instead place the lock indicators in between the key split. Some brands of keyboards have a function mode key (also called F mode or Office Lock), and may replace the scroll lock indicator with an office lock indicator. Office Lock, when enabled, will enable alternate functions of the function keys, meant for use with various word processing or email programs.


...
Wikipedia

...