This book gives a comprehensive account of Maude, a language and system based on rewriting logic. Many examples are used throughout the book to illustrate the main ideas and features of Maude, and its many possible uses. Maude modules are rewrite theories. Computation with such modules is - cient deduction by rewriting. Because of its logical basis and its initial model semantics, aMaudemodulede?nesaprecisemathematicalmodel.Thismeans that Maude and its formal tool environment can be used in three, mutually reinforcing ways: - as a declarative programming language; - as an executable formal...