The book is so that principles can be easily and quickly referenced by name. For those interested in addressing a specific problem of design, the (How can I help people learn from my design? How can I enhance the usability of a design? How can I make better design decisions? ...). Each principle is presented in a two-page format. The left-hand page contains a , a , , and . Side notes appear to the right of the text, and provide elaborations and references. The right-hand page contains and related graphics to support a deeper understanding of the principle. This landmark reference is the standard for designers, engineers, architects, and students who seek to broaden and improve their design expertise.