This comprehensive 2020 textbook delves into the fundamental principles and practical implementations of modern database systems. Co-authored by Prof. Alaa Al-Hamami and Dr. Saad Al-Ani, it covers essential topics like relational models, SQL, database design, normalization, and security. It is designed for students and professionals seeking a solid understanding of how to effectively design, manage, and utilize databases, bridging the gap between theoretical knowledge and hands-on application. The text is enriched with examples and case studies to reinforce learning.