The Mouse

A mouse is almost exclusively used in conjunction with a keyboard as part of a WIMP Graphic User Interface. The mouse is moved and the speed and direction of movement are echoed in the movement of a pointer on the VDU screen. This is achieved by using a rubber coated ball which cause two movement sensors to be activated. More modern mice use reflected light to detect movement. This overcomes the problems of dirt and fluff blocking up the mechanism.

Buttons on the mouse can be used to pull menus that the pointer is on down or to select menu options.

A mouse can be used to input data for drawing or graphic design programs. Again a pointer or similar icon is moved around the screen as the mouse is moved by the user.

The mouse is useful for inputting both relative movement and speed of movement. It does not however provide data about absolute positions. In other words the computer can detect how far left or right the mouse has been moved but it will not know whereabouts the mouse is on the desk.

One problem with using a mouse is that it needs a flat surface to move over. This has led to the use of a small roller ball on laptop computers where there may be no suitable surface available for a mouse.

Mice are very susceptible to dust and dirt which makes them produce erratic data, causing the pointer on the screen to jump rather than move smoothly. This can be prevented by regular cleaning and the use of a mouse mat. Most users now use a mouse that calculates its position by the use of an infa-red light and a sensor. The ball mouse will be obsolete with in five years

There is increasing interest in the use of cordless mice and keyboards which link to the computer with infra-red radiation thus allowing the user to position the hardware with greater freedom.

© LEV