Each module has a .txt with the details of the Kata example as well as it's own ReadMe with some helpful links about the languages & their unit-test libraries. The Kata example that each follows is Roy Osherove's String calculator. You can find more information about Osherove and his other Kata examples here: http://osherove.com/
These sample projects are designed to help you get started with trying out TDD. Use these projects to explore and try out different design pattern, libraries, or just poke around the languages to see what they really do. Just be sure to follow the red - green - amber pattern and time yourself to make sure that you stay on track on your investigations. Enjoy!