Software Defect Classification, Defect Life Cycle & Defect Reporting

This unit explores how defects are identified, classified, and managed throughout the software testing process. It begins with the core definition of a defect and how it differs from a bug, followed by a detailed classification into requirement, design, coding, and testing defects, each broken down into further sub-types. The defect management process is explained through its key stages — prevention, discovery, resolution, and process improvement — alongside the complete defect life cycle from open to closed status. A practical defect report template with a worked example helps illustrate how real-world defect tracking works, along with an explanation of each attribute like severity, priority, and status. The notes conclude with static, dynamic, and operational techniques used to uncover defects. This unit is especially useful for understanding how testing teams document, prioritize, and resolve issues in a structured, professional manner.