Test Driven Development (TDD) is a software development methodology where developers write tests before they write the actual code. The process typically involves writing a failing test case, writing the minimum amount of code necessary to pass the test, and then refactoring the code to improve its structure without changing its behavior. TDD follows a cycle known as the "Red-Green-Refactor" cycle.

1. **Red**: Write a failing test case that defines the desired behavior of a piece of code.

2. **Green**: Write the simplest code that makes the test pass.

3. **Refactor**: Clean up the code while ensuring that all tests still pass.

The primary goal of TDD is to ensure that the code meets the requirements and behaves correctly according to the specified tests. This approach helps in creating more robust, maintainable, and bug-free code. TDD encourages developers to think about the design and architecture of their code upfront, leading to better software design and fewer defects.

Some benefits of Test Driven Development include:

1. **Faster feedback loop**: Developers get immediate feedback on whether their code behaves as expected.

2. **Improved code quality**: TDD encourages writing modular, testable, and loosely coupled code.

3. **Reduced debugging time**: By catching bugs early in the development process, TDD helps reduce the time spent on debugging.

4. **Increased confidence**: Having a comprehensive suite of tests gives developers confidence to make changes to the codebase without fear of breaking existing functionality.

5. **Better documentation**: Tests serve as executable documentation, providing insights into the intended behavior of the code.