This book provides a comprehensive overview of software engineering, exploring what software is and its significance in modern life. It delves into the role of software engineers in building and supporting software that is widely used across various industries. The text discusses the importance of software in our daily activities, commerce, and culture, emphasizing its pervasive nature. It also examines the steps involved in the software development process, from identifying customer needs to software application in solving specific problems. Additionally, the book explores the unique characteristics of software deterioration and maintenance compared to hardware. Various software application domains are explored, including system software, application software, engineering/scientific software, embedded software, product-line software, web/mobile applications, and artificial intelligence software.