This book, first published in 1974, provides a comprehensive guide to the COBOL programming language, a vital tool in the development of business and commercial applications from the 1960s onwards. It covers not just the fundamentals of the language, including its syntax, semantics, and structure, but its application across a variety of practical domains, from data handling to report generation, file organization, and debugging techniques. This book is a valuable historical resource for programmers interested in the evolution of COBOL and its enduring legacy in the development of modern software applications.