A mouse is a pointing device that controls the movement of the cursor on a computer's display screen. It's one of the primary computer accessories. In fact, many computer users don't know how use their computers without the aid of their mouse. As a key computer component, it's often used for long amounts of time. Prolonged use of mice sometimes leads to problems such as muscle fatigue, inflammation, strained shoulders and elbows, and Carpal Tunnel Syndrome. These ailments and computer-related injuries are precisely what an ergonomic mouse seeks to prevent.
A mouse becomes an ergonomic mouse when it is comfortable and easy to use, both physically and psychologically. Not all mice are like that, however. Ergonomic mice have been specially designed by engineers, doctors, and other professionals to reduce fatigue and repetitive stress imposed on your wrist, hand, and arm.
The increased comfort of an ergonomic mouse leads to greater productivity for the user. In fact, some ergonomic mice boast that they will keep your hand in an "optimal work zone."
A common trait among different ergonomic mice is the fact that they keep the hand in a more natural position and neutral angle, as opposed to the ordinary mouse that requires you to twist your forearm. This position is often billed as a "handshake position" — a term that will come up a lot when you're searching for ergonomic mice.
Beyond that, different products add different features. Some boast of additional buttons that are programmable with different functions. Some have adjustable sizes while others take a "one shape fits all hand sizes" approach. Some stick to the regular horizontal shape, while others go for the "vertical grip." Others still have built-in palm supports, scroll wheels, optical sensors, built-in trackballs, and soft-touch materials.
An ergonomic mouse can also come in left- and right-hand variants, as well as cabled and cordless. Many are compatible with different operating systems such as Windows, Mac OS X, and Linux. For maximum ease and comfort, the ergonomic mouse can be teamed up with other ergonomic computer devices, including ergonomic keyboards, ergonomic mouse pads, wrist rests, and arm supports.