Give clear indications for orientation. Take care to relieve the memory while navigating. Ensure freedom of action and decision at any given moment. It should be possible to undo any user action . Give preference to visual feedback .
Immediate feedback enhances user-machine communication .
Waiting can be annoying and disturbing. For all functions of a program provide several different ways of starting them. Exclude mistakes wherever possible Keep presentations sober . The expectations of users concerning interface quality and ease of use are constantly rising. This is partially due to the rapidly evolving calculation speed of the chips.