Mouse button

A mouse button is a microswitch on a computer mouse which can be pressed (“clicked”) to select or interact with an element of a graphical user interface.

The three-button scrollmouse has become the most commonly available design. As of 2007 (and roughly since the late 1990s), users most commonly employ the second button to invoke a contextual menu in the computer's software user interface, which contains options specifically tailored to the interface element over which the pointer currently sits. By default, the primary mouse button sits located on the left-hand side of the mouse, for the benefit of right-handed users; left-handed users can usually reverse this configuration via software.

In contrast to its motion-tracking mechanism, the mouse's buttons have changed little over the years, varying mostly in shape, number, and placement.

A mouse click is the action of pressing (i.e. 'clicking', an onomatopoeia) a button to trigger an action, usually in the context of a graphical user interface (GUI). “Clicking” an onscreen button is accomplished by pressing on the real mouse button while the pointer is placed over the onscreen button's icon.

The reason for the clicking noise made is due to the specific switch technology used nearly universally in computer mice. The switch is a subminiature precision snap-action type; the first of such types were the Honeywell MICRO SWITCH products.

Double clicking refers to clicking (and, naturally, releasing) a button (often the primary one) twice. Software recognizes both clicks, and if the second occurs within a short time, the action is recognized as a double click.

If the second click is made after the time expires it is considered to be a new, single click. Most modern operating systems and mice drivers allow a user to change the speed of a double click, along with an easy way to test the setting. Some software recognizes three or more clicks, such as progressively selecting a word, sentence, or paragraph in a word processor text page as more clicks are given in a sequence.

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