Käännynnäppäin

Käännynnäppäin, also known as a toggle key or sticky key, is a feature found on computer keyboards and some other input devices that allows users to lock certain modifier keys into an active state. This means that keys like Shift, Control, Alt, or the Windows key can be pressed once to activate their function, and they will remain active until pressed again. This differs from standard modifier key behavior, where the key must be held down simultaneously with another key to perform a function.

The primary purpose of käännynnäppäin is to assist users who have difficulty performing simultaneous keystrokes or holding down multiple keys at once. This can include individuals with certain physical disabilities or those who find the standard method ergonomically challenging. By activating käännynnäppäin, these users can press modifier keys sequentially rather than simultaneously, making complex keyboard shortcuts more accessible.

Käännynnäppäin functionality is typically accessed through accessibility settings within the operating system. Once enabled, users can often configure how the keys behave, such as whether they activate on a single press or after a short delay. The visual feedback for activated käännynnäppäin keys might include an on-screen indicator or a change in the physical key's light, if available. While beneficial for accessibility, it's important to note that inappropriate activation of käännynnäppäin can interfere with normal typing and key combinations.