Do you ever get fed up of
taking your hand off the keyboard and onto the mouse/mouse pad;wiggling the pointer on the screen so that you can find it;moving it to the right place;clicking;moving your hands back onto the keyboard, and thenfinding your home keys again ready to do the next bit of typing?Are you a competent typist and find that using the mouse slows you down? Do you have a laptop but find it extremely annoying thave to use that track pad? Maybe you have a mobility problem such as Repetitive Strain Injury (RSI) which is exacerbated by using the mouse? Or do you have co-ordination problem which makes using the mouse all but impossible? Do you have a sight problem and can't see the mouse pointer anyway?