Let's Code: Test-Driven JavaScript, my screencast series on rigorous, professional JavaScript development, recently celebrated its one year anniversary. There's over 130 episodes online now, covering topics ranging from test-driven development (of course!), to cross-browser automation, to software design and abstraction. It's incredibly in-depth and I'm very proud of it.

To celebrate the one-year anniversary, we've released Object Playground, a free video and visualizer for understanding object-oriented programming. The visualizer is very cool: it runs actual JavaScript code and graphs the object relationships created by that code. There are several preset examples and you can also type in arbitrary code of your own.

Object Playground in action

Understanding how objects and inheritance work in JavaScript is a challenge even for experienced developers, so I've supplemented the tool with an in-depth video illustrating how it all fits together. The feedback has been overwhelmingly positive. Check it out.