Dojo Toolkit Reference Guide
The base functionality of the Dojo Toolkit, provided by just including dojo.js. This includes tons of features like CSS-based queries, event handling, animations, Ajax, class-based programming, and a package system that makes getting access to the rest of Dojo a snap.
Additional stable (but optional) components for advanced animations, I/O, data, Drag and Drop and much more.
Dijit is Dojo's themeable, accessible, easy-to-customize UI Library. There are many widgets to choose from, so be sure to check out the quickstart guide which covers the basics. Dijit requires dojo.js and other Core modules.
DojoX stands for Dojo eXtensions and contains many useful sub-projects and varying states of maturity -- from very stable and robust, to alpha and experimental. All DojoX projects contain README files that outline their maturity and authorship, so be sure to check those along with the documentation pages to get the full picture of where a module is headed.
DojoC is an external svn repository used by DojoCampus for a variety of widgets, tutorials, sandbox, and other demos. You are welcome to explore and contribute, though absolutely nothing is guaranteed to work. DojoC is meant as a community workshop, and code comes and goes frequently, often times 'promoted' to DojoX projects.
Dojo uses a custom inline comment syntax which produces well structured xml, and powers the official API Docs .