This is an era of rapid technological advancements. The software development technology has also grown by leaps and bounds. We have been able to build applications that were diffi cult if not impossible just a short time ago. However, with the technological advancement and increase in user requirements, a need to build large and complex software system also arose. In these large and complex software systems, effi cient organization of data plays an important role. There are various data structures available for organizing data depending upon the type of applications. The choice of any data structure depends on its simplicity and effectiveness in processing of data. The main aim of this book is to provide better understanding of various data structures. The discussion is well supported by fi gures and programming examples. The examples are kept simple and concise for better understanding of the concepts and methods. The book discusses both introductory and advanced topics of data structures using C and is specifi cally designed to meet the requirements of III semester BTech students of GTU. In this book, each chapter addresses the specifi c data structure like stacks, queues, trees, etc. The structure of the book is given herein.