Test Driven Development (TDD) using the QUnit framework. TDD involves writing test cases before writing code to pass those tests. This ensures code quality and prevents regressions. QUnit is a JavaScript unit testing framework that allows writing test cases and making assertions. Practicing TDD with QUnit involves writing unit tests, running them, then writing code to pass the tests, and refactoring code as needed. TDD results in more maintainable, robust code and a documented test suite for new developers.