What is TDD?

Definition

An agile methodology in which unit Tests Drive the Development of consequent code.

TDD In Practice

• SPECS: Break up your task into functional units
• UNIT TESTS: Write tests for each functional unit
• FAIL: Run the tests, see them fail
• CODE: Write the code
• PASS: See the tests pass as you fill out the functional units

(Inspired by Evan Dorn, and Simon Allardice: cf. Links)