The patterns in this paper use examples drawn from a simple booking system for an arts centre. The initial brief for this system is as follows:
Design a program for a booking office of an arts centre. There are several theatres, and people may reserve seats at any theatre for any future event. People need to be able to discuss seat availability, where seats are located, and how much they cost. When people make a choice, the program should print the price, record the selection, and print out a ticket.
Typically, we would expect to have much more information (either more text, or at least the opportunity to talk to the project sponsor). We will introduce more details as the example progresses.