The really nice thing is that the site is very keyboard friendly. There are shortcuts to jump to each section, and also shortcuts to flip over to the different tabs. They intelligently put those tabs along top so that you can make full use of the vertical space to focus on just one of the different code types.
You can also see in the screenshot above the nice indentation and syntax highlighting, which was all done by the site to help keep things a little more organized. Plus in the case of the HTML Tinkerbin will even highlight tags that aren’t matched.