What is the purpose of "unit testing"?

"Unit testing" is a software testing technique that focuses on verifying and validating the functionality of individual components or "units" of a program. By concentrating on the smallest testable parts of an application, such as functions or classes, developers can ensure that each piece behaves as expected before integrating it with other components. This early identification of bugs or issues contributes significantly to overall code quality and maintainability.

The key advantage of unit testing lies in its ability to isolate specific sections of code, enabling developers to pinpoint where issues arise and make necessary adjustments efficiently. Since unit tests are automated and can be run frequently throughout the development process, they serve as a safety net that helps maintain the integrity of the code as changes are introduced.

In contrast, other options like deploying software applications, writing documentation, or gathering user feedback do not describe the specific function of unit testing. These activities serve different purposes within the software development lifecycle and do not focus on the individual units of code that unit testing aims to validate.