But for Dr. George E. Gerpheide, an engineer, it is an abomination. He set out to build, if not a better mousetrap, then something to rid society of the inelegant mouse. His solution was an electronic touch pad that would register the slightest twitch of a finger and translate it into cursor movements on the monitor. Apple was the first to license Gerpheide's technology and take it to market. Most laptop manufacturers, with the exception of IBM and Toshiba, which employ a joystick, have adopted touch pads.
Touch pads range from the size of a pack of matches to that of a small wallet.
They rely on minute flows of electric current and how those currents are modified by the human finger's effect on small electric fields, so moisture or electromagnetic interference can diminish performance. That was particularly true of early touch pads. They also do not need to make space on their desks for a mouse to roam in. Unlike touch screens and some touch pads called resistive, which require pressure from a finger or stylus to function, one need not actually touch the surface of a capacitive touch pad to make it work. The finger can affect electric fields in the touch pad even when it is merely near the surface.