In the past, you did not work with the mouse, but with key combinations and with the arrow, page-down and page-up keys. By activating Scroll Lock, you could use these buttons to inspect a part or the lower end of a text or program code without moving the cursor away from where it was. Today, Scroll Lock is practically no longer used, even if, according to Wikipedia, there are still individual programs that rely on Scroll Lock. Most users are at most surprised by strange phenomena in selected programs when they accidentally activate the button. In Excel, for example, Scroll Lock still has the effect described today. If you drive down a spreadsheet using the arrow keys without Scroll Lock (read: in normal mode), the cell marking moves downwards. The table remains until you reach the bottom; the table then scrolls so that you can still see the marking. The marker remains in the picture. With the Scroll Lock activated, however, Excel behaves very differently when you scroll down using the arrow key: The selection remains in the cell that you originally clicked on – and the table scrolls up or down together with the fixed selection. In exceptional cases, this can even be useful for one or the other hand movement – it is usually rather annoying: You can no longer move the cell marking with the arrow keys, but have to do it with the mouse.