The study of Data Structures and the Algorithms that manipulate them is one of the most fundamental concepts in the field of Computer Science. This book aims at providing a comprehensive introduction to various data structures and their implementation. All the programs are implemented in C language, henceforth the prior knowledge of C language is a must to read and understand this book.The concepts of data structure are so very important that most of the other subjects in computer science rely on data structures. All the programs in this book have been tested thoroughly and debugged. Sufficient care is taken to maintain the simplicity on the concepts to meet the requirements of students who are just exposed to the concept of data structures. This book is ideally suited for undergraduate students of Engineering, Science, Diploma and MCA.The key topics covered in this book are:Stack and its applications like conversion of expression, Evaluation of postfix expression and recursion.Circular queue implementationLinked list and their application in polynomial addition.Binary tree implementationHashing with linear probing.Graph traversal method like BFS and DFS