This second edition describes C as defined by the ANSI standard. This book aims to help the reader learn programming in C. It assumes a certain familiarity with basic programming concepts such as variables, assignment statements, loops, and functions. An inexperienced programmer should be able to follow along and learn the language.

All examples have been tested and are provided in machine-readable form. Various aspects of C are covered in detail, with an emphasis on complete program examples rather than isolated fragments. It addresses fundamental data types, operators, and expressions. It covers functions and program structure, external variables, scope rules, multiple source files, and also touches on the preprocessor. It also describes an interface between C programs and the UNIX operating system, focusing on input/output, the file system, and memory allocation. Additionally, it offers a language reference manual. The official statement of the syntax and semantics of C is the ANSI standard.