The present book is the fourth enlarged edition of the earlier book A Text Book of Logic-An Introduction. The current edition includes an additional chapter on Uses of Language and its Functions. Like the earlier book, the present book sets forth the principles and procedures of elementary Logic in the most simplified way and is specifically designed and intended for the use of undergraduate students. It contains almost all the main topics on Deductive, Inductive and Symbolic Logic prescribed in the syllabi of different universities in the country. The book attempts to present a clear perspective on Logic as a science of correct reasoning. In the introductory chapter the aim of Logic and the task of a Logician are elaborated. Other topics covered here are Terms, Propositions, Immediate Inference, Syllogism, Boolean Equations, Venn Diagrams, Anti-Logism Theorem, Truth Functions, Truth Table, Deductive Method, Predicate Calculus, Scientific Inductions, Causation, Mill's Methods and Informal Fallacies to mention a few. All the topics are explained with the help of diagrams and lucid examples. Each chapter is followed by plenty of exercises for the benefit of students.