Book excerpt: This popular handbook presents a step-by-step method for clearly explaining a product, system, or procedure. The easy-to-follow text--packed with examples and illustrations--explains the unique demands of this form of writing and shows how to set up the best user model. The book covers developing a modular outline and storyboard, generating the draft, revising, developing a formal usability test, and supporting and updating user documentation. Also included are a glossary of terms, a listing of books and periodicals for additional information, and an index.