keyboard上的 ”Scroll Lock”有咩用

On PC keyboards, a key used to toggle between a scrolling and non-scrolling mode. When on, the arrow keys scroll the screen regardless of the current cursor location. This key is rarely used for its intended purpose, if at all.

Scroll lock is a key (often with an associated status light) on most modern computer keyboards. The behavior of the key depends on the particular software in use.

The scroll lock key is a remnant from the original IBM PC keyboard. In the original design, scroll lock was intended to modify the behavior of the arrow keys. When the scroll lock mode was on, the arrow keys would scroll the contents of a text window instead of moving the cursor. In this usage, scroll lock is a modifier key like Alt and Shift (which modify the function of other keys) and, more specifically, a toggling lock key like Num Lock or Caps Lock, which have a state that persists after the key is released. Today, this particular use of scroll lock is rare. Only a few modern programs still honor this behavior, such as Microsoft Excel (in the behavior of arrows — when scroll lock is on, the selection does not move), Lotus Notes and Forté Agent. In modern GUI environments, scrolling is usually accomplished using means such as scrollbars or scroll wheels. Therefore scroll lock can be regarded as a defunct feature in almost all modern programs and operating systems; some keyboards lack scroll lock altogether.

Scroll lock has fallen into such extremely infrequent use that some of the lighter-weight Linux desktop environments, such as Xfce, don't support it at all.

use it for locking the scroll bar. when scroll lock is on, you cannot scroll down the screen using the arrows or "Page up", "Page down"