Every extra unit of information in an interface competes with the relevant units of information and diminishes their relative visibility.

#6: Recognition rather than recall Minimize the user's memory load by making elements, actions, and options visible. The user should not have to remember information from one part of the interface to another.

Good error messages are important, but the best designs carefully prevent problems from occurring in the first place. Either eliminate error-prone conditions, or check for them and present users with a confirmation option before they commit to the action.

#3: User control and freedom Users often perform actions by mistake. They need a clearly marked "emergency exit"

#2: Match between system and the real world The design should speak the users' language. Use words, phrases, and concepts familiar to the user, rather than internal jargon.

#1: Visibility of system status The design should always keep users informed about what is going on, through appropriate feedback within a reasonable amount of time.