What is unit testing?

Unit testing refers to the practice of testing individual components or modules of a software application to ensure that each part functions correctly and as intended. This method focuses on small, isolated pieces of the code, typically functions or methods, allowing developers to verify the correctness of each component before integrating them into larger systems. By conducting unit tests, developers can catch errors early in the development process, making it easier to identify and fix issues before they propagate to more complex interactions within the application.

This practice can significantly improve software reliability and reduce the cost and time associated with debugging later stages of development. It serves as a foundational step in software testing, ensuring that the building blocks of the application behave as expected.