14.6. Other Object Design Techniques: CRC Cards
People prefer different design methods because of familiarity and, quite significantly, because of different cognitive styles . Don't assume that icons and pictures are better than text for everyone, or vice versa.A popular text-oriented modeling technique is Class Responsibility Collaboration (CRC ) cards, created by the agile, influential minds of Kent Beck and Ward Cunningham (also founders of the ideas of XP and design patterns).CRC cards are paper index cards on which one writes the responsibilities and collaborators of classes. Each card represents one class. A CRC modeling session involves a group sitting around a table, discussing and writing on the cards as they play "what if" scenarios with the objects, considering what they must do and what other objects they must collaborate with. See Figure 14.2 and Figure 14.3.