This book covers most of the basic topics of Data Structures. The logic behind every program of data structures with inclusion of flowcharts, pseudo codes and programs. The programs are written by using the concepts of object oriented programming language in C++ which are verified and tested. The topics covered in this book are linked list, stacks, queue, binary tree, threaded binary tree, traversals – BFS & BFS, different sorting methods, hashing and AVL. We have also explained the basic concepts of OOPs. In this book, we have explained the hashing and AVL and we expect that students will try to write the small programs in these topics as well. Individual topics of programs cover the pseudo code, diagrammatic representation and the concepts of that particular topic. We have tried to explain the topics in a very simple manner and we hope that the students will be able to understand the topics well. We would suggest that after going through the entire concepts of data structures, every student should try to solve the assignment given at the end of this book and I am very sure that if student does this exercise, he will never forget this subject and will start loving this subject. With this exercise, not only the basics of data structures but also their concepts of different programming languages will also be made stronger. Our best wishes to the students….