The document provides an overview of fundamentals of software development including definitions of software, characteristics of software, software engineering, layered approach to software engineering, need for software engineering, and common software development life cycle models. It describes system software and application software. It outlines characteristics like understandability, cost, maintainability, modularity, reliability, portability, documentation, reusability, and interoperability. It also defines software engineering, layered approach, and need for software engineering. Finally, it explains popular life cycle models like waterfall, iterative waterfall, prototyping, spiral, and RAD models.