BEHAT is an automated testing framework for PHP. Behat is used for functional testing. Behat is open source as well as it can be expanded using extensions. It works on the principle, Behavior Driven Development. Behat requirement documents are written in a language called Gherkin. Gherkin is plain English formatted in a specific way so that the Behat software can parse it. It will require programmers support to implement it.
More information is available at Behat Official website.