ABSTRACT
In an attempt to provide a better user experience, electronic products these days provide a graphical user interface. The complexity of the interface depends on the product and its usage scenario. For instance, consider these devices: a DVD/MP3 player, a mobile phone, and a PDA. A DVD/MP3 player requires some form of primitive interface that is capable of listing the CD/ DVD contents. Creating playlists and searching tracks would be the most complex of operations that can be done on a DVD/MP3 player. Obviously this is not sufficient for a mobile phone. A mobile phone has more functionality. The most complex requirement is in the PDA. One should be able to run almost all applications such as word processors, spreadsheets, schedulers, and the like on a PDA.
