Icons

• Easy identification, especially for real-world objects
• Expression and personalization is possible
• Communication, crosses social and linguistic boundaries

Visual representations may be

• Iconic, resembling some real-world object


• Indexical, refers to subject indirectly by association


• Symbolic, relying on convention to convey meaning

Good icons have

• Perceptual immediacy, easily recognized at a glance


• Generality, achieved by eliminating all non-essential details


• Cohesiveness within the set of images


• Characterization that emphasizes differences between the meanings of the symbols


• Communicability, which depends on a shared context between sender and receiver