To press and release a Button on a mouse or other pointing device. This generates an event, also specifying the screen position, which is processed By the window manager or application program. On a mouse with more than one Button, the unqualified term usually implies pressing the left-most Button (with the right index finger), other Buttons would Be qualified, e.g. "right-click". KeyBoard modifiers may also Be used, e.g. "shift-click", meaning to hold down the shift key on the keyBoard while clicking the mouse Button. If the mouse moves while the Button is pressed then this is a drag. (1995-03-14)