This book provides a survey of the major approaches to structural linguistics that developed in the 20th century. It summarizes theories from the Prague School, Copenhagen School, American structuralism, functional linguistics, and transformational grammar. The book also examines topics like mathematical linguistics and machine translation. It compares key concepts and debates between different scholars and linguistic traditions. Overall, the book aims to give readers a comprehensive but concise overview of the different traditions within structural linguistics and how they relate to one another.