BDD testing is an Agile approach to software testing where testers write test cases in simple language that even people without technical expertise can understand. The goal of BDD testing is to increase collaboration between the technical side and the business side. The Gherkin language is a unique business-readable language used to describe system behaviors and scenarios. It is structured by 3 primary statements: Given - When - Then, with each statement describing a specific aspect of the system.

TDD (Test Driven Development) and BDD (Behavior Driven Development) are fairly similar development approaches that both emphasize testing and collaboration, yet have major differences in focus and methodology. Simply put, in TDD, developers test first, then use the test results to guide their development, while in BDD, developers express the system behavior they want to create through Gherkin syntax, then code according to those Gherkin expressions.