This is a textbook on software specification emphasizing formal methods that are relevant to requirements and design stages of software development. The aim of the book is to teach the fundamental principles of formal methods in the construction of modular and verifiable formal specifications. The book introduces several formal specification techniques and illustrates the expressive power of each technique with a number of examples. General Characteristics Traditional textbooks on software engineering discuss the difficulties and chal lenges that lie on the path from requirements analysis to implementation of a software product. Most of these books describe some techniques in detail and give hints on implementation of these techniques. Only a few among them deal with important software engineering principles and techniques, and discuss how a particular technique may be used to implement a given principle. There is very little exposure in these books to a rigorous approach to, or a systematic study of, the construction of verifiable software. Those who have acquired an understanding of the fundamental principles of software engineering from traditional textbooks will find the following characteristics of this book quite relevant to the practice of software engineering: • The book deals with specification. The principal characteristic of this book is to discuss formalisms that provide a theoretical foundation for the principles of software engineering, and are appropriate to the requirements and design stages of software development.
