This book shows how to create parsers and the language applications built on top. Introducing ANTLR and Computer Languages, Meet ANTLR, A Starter ANTLR Project, Developing Language Applications with ANTLR Grammars, Exploring Some Real Grammars, Building Some Real Language Applications, Advanced Topics, Attributes and Actions, Wielding Lexical Black Magic, ANTLR Reference, Removing Direct Left Recursion, Grammar Reference, Bibliography.