One-quarter the length and price of conventional textbooks, this popular introduction to technical writing teaches the essentials with remarkable economy, clarity, and authority.   The book is divided into two parts. Part One focuses on the seven fundamental principles of good technical writing, such as knowing one's purpose and audience, thinking visually, and writing ethically. Part Two covers the formats of reports and correspondence.   The Elements of Technical Writing concentrates on the essentials, providing readers with precisely the information needed to produce effective technical documents and no more.