yt provides a great deal of functionality to the user, but sometimes it can be a bit complex. This section of the documentation lays out examples recipes for how to do a variety of tasks. Most of the early, simple code demonstrations are small scripts which you can easily copy and paste into your own code; however, as we move to more complex tasks, the recipes move to iPython notebooks to display intermediate steps. All of these recipes are available for download in a link next to the recipe.
All of the data used in the cookbook is freely available here, where you will find links to download individual datasets.
To contribute your own recipes, please follow the instructions on how to contribute documentation code: How to Write Documentation.