Behavior Driven Development (BDD) is a software development approach that emphasizes collaboration and communication between developers, stakeholders, and customers to build software that meets the needs of the business. BDD is an evolution of Test-Driven Development (TDD) and focuses on writing tests that describe the desired behavior of a system, rather than just testing its implementation.

Test First Development (TFD), also known as Test Driven Development (TDD), is a software development approach where tests are written before writing the actual code. The idea behind TFD is to write tests that describe the desired behavior of the code and to use those tests to drive the design and implementation of the code.