A good place to start is the API documentation which documents the functions and classes exposed by Luvit. We also have examples!
Functions with similiar names may have more detailed explanations in the Nodejs docs.
Luvit also comes with a package manager, similiar to npm.
LibUV bindings for lua. Will work without luvit. Luvit wraps a lot of functionality from it.
Luv with conventions. The base for making standalone executables.
Reading source code is always fun!
The following clickable map shows the relationships between the various parts of the luvit ecosystem in case you get lost.