Refactoring is the process of restructuring existing code without changing its external behavior to improve its readability, maintainability, and extensibility. The goal of refactoring is to clean up code, reduce technical debt, and enhance the overall quality of the software, making it easier to understand, debug, and modify. Common refactoring techniques include renaming variables or methods to be more descriptive, breaking down large functions into smaller, more focused ones, removing redundant or duplicated code, and improving code organization by applying design patterns.

Refactoring is typically performed as part of continuous improvement during the development process, especially in Agile environments where codebases evolve rapidly. By regularly refactoring, developers can prevent code rot, where the codebase becomes increasingly difficult to work with over time due to accumulated inefficiencies or poor practices. While refactoring does not add new features to the software, it is a critical practice for ensuring the long-term health and sustainability of a codebase, enabling teams to deliver high-quality software that is easier to extend and maintain.