There's lots and lots of information on Test Driven Development (TDD) on the web. Much of it is very useful, but many people still don't get the primary point.

• Test Driven Development is a design technique, not a testing technique.

Sure, you end up with a UnitTest suite that can be very useful for testing and provide a framework for adding tests. This is a wonderful benefit of TDD, but it's not what TTD is.

• "That's what a ship is, you know. It's not just a keel and hull and a deck and sails. That's what a ship needs. But what a ship is... is freedom." (Captain Jack Sparrow, from Walt Disney's Pirates of the Caribbean: The Curse of the Black Pearl)

Test Driven Development is also freedom. It's the freedom to change your mind. It's the freedom to move forward without worrying that you're making a mistake. It's the freedom to concentrate on what you want rather than how to build it.

ToBeWritten:

• The change of viewpoint required to do TDD.
• How the tests generated by TDD are "free," coming out of design time that is necessary in any case.
• Why I don't want to write software without TDD, ever again.
• How to get started with TDD.
  • Greenfield development
  • Legacy development
    • Potential code bases

    • [http://columba.sourceforge.net/ Columba] email client, has some unit tests but doesn't look like complete coverage, a little big and complex for an example (broken into multiple projects built with Maven).

    • [http://sourceforge.net/projects/jabref/ JabRef] bibliographic database, has some unit tests, needs some refactoring for clarity, in any event.

    • [http://xplanner.org XPlanner] might be a possibility.

    • [http://jgnash.sourceforge.net/ JGnash] is a java personal finance program, has some unit tests (JUnit 4, Java 5)

    • [http://sourceforge.net/projects/jmoney/ JMoney] is a java/Eclipse RCP personal finance program

    • [http://sourceforge.net/projects/nomadpim/ Nomad PIM], Java 5, has test suite

Elsewhere:

• Emmanuel Gaillot's [http://emmanuelgaillot.blogspot.com/2006/03/explaining-tdd-to-your-baker.html Explanation of TDD] to his baker.

• Michael Feather's [http://www.artima.com/weblogs/viewpost.jsp?thread=126923 A Set of Unit Testing Rules] "A test is not a unit test if..."

• M Easter's [http://codetojoy.blogspot.com/2007/02/im-believer.html Dining at the TDD Buffet] blog entry.

• Ed Gibb's [http://edgibbs.com/2007/05/05/test-driven-development-applied/ review] of Lasse Koskela's book, Test Driven: TDD and Acceptance TDD for Java Developers (1932394850)

• Christoph Steindl's [http://www.agilealliance.org/system/article/file/1423/file.pdf Test-Driven Development] slides