We are pleased to present this textbook titled “Data Structure I” for the course CS-201-MJ-T offered in Semester III of S.Y.B.Sc. (Computer Science) under the Savitribai Phule Pune University (SPPU) curriculum. This book has been developed in alignment with the NEP CBCS 2025–26 syllabus and aims to provide students with a solid foundation in data structures, their implementation, and their applications in solving computational problems.

 Data structures are a fundamental component of computer science. They provide systematic ways to organize, manage, and process data efficiently. This subject helps learners bridge the gap between basic programming skills and advanced problem-solving techniques required in software development. Each chapter has been written in simple language, supported by diagrams, algorithms, and example programs in C to strengthen understanding. The book emphasizes not only theoretical concepts but also the practical implementation aspects that are crucial for developing real-world applications.

We are thankful to our vibrant publisher Shri Rangrao Patil and all staff of Prasant Publications for their efforts and keen interest in publishing this book in a very limited span of time. We hope that this textbook will serve as a helpful companion to students and teachers alike in their academic journey, and will encourage learners to think analytically and solve problems effectively using appropriate data structures. We welcome constructive suggestions and feedback from readers to improve future editions of this book.