1.Visibility of System Status
–Always keep users informed about what is going
on.
–Provide appropriate feedback within reasonable
time.
2.System Matches Real World
–Speak the users'
language, with words, phrases and concepts familiar to the user, rather than
system-oriented terms.
–Follow real-world
conventions, making information appear in a natural and logical order.
3.User Control and Freedom
–Users often choose system functions by
mistake.
–Provide a clearly marked "out" to
leave an unwanted state without having to go through an extended dialogue.
–Support undo and redo.