•Developed in the 1960s at
Stanford Research Institute
•became commercially
widespread in the mid-1980s when it was
sold as part of the MacIntosh™
•Advantages: can be used by
either hand, causes relatively little fatigue,
is physically robust, and has convenient
finger selection buttons, and can position in different locations
•Disadvantages: associated
with substantial wrist extension
postures (25-30°) and carpal tunnel
pressures (up to 18.7 ± 3.8 mmHg) (Keir et al., 1999), physical area required when using a mouse is larger than ideal