ABSTRACT
The use of portable computers has grown continuously, especially since the nature of work environment is changing and many companies profit from the advantage of mobile workforce. This development places more emphasis on functional and effective notebook technology as well as a more natural and easy communication with interactive systems. Currently, two different input devices integrated in notebooks are available. The trackpoint is a small, force sensitive isometric joystick, and the touchpad which is a touch sensitive panel. Since technical design, location and size of internal input devices are restricted to the chassis, ergonomic requirements and suitability of interaction distinguish integrated and optional input devices (e.g. mouse, trackball, tablet, pen). In the discussion about usability of input devices two important factors have to be named first: The performance potential of input devices which is limited by technical and physical features and the users themselves with their input technique as the decisive factor for the degree of utilization.
