The purpose of this activity is to explore aspects of visibility in design. Suppose you're designing an interface for two players to play checkers (also called draughts) across the Internet. The picture on the right shows the scenario: each player has an interface on their screen, and the state of the game is stored on a network server that both communicate with.

Guided by the categories below, make a list of what needs to be made visible, and then brainstorm (and sketch) how the interface might make it visible.

• Actions: what can the user do?
• State: what is the current state of the system?
• Feedback: what was the effect of the user's action?