If you use certain FOM methods they will return a Node object. In fact, every Node object in APP is actually an fxNode. It is fully documented in the FOM documentation that ships with APP, and if you read W3C DOM Level 2 you will find all the information about the basic DOM support which APP extends.
BTW, from memory, I think the Help Center in v10 and possibly early v11 was missing all the information about DOM. If you find that to be the case, you can build your own FOM documentation using the FOM Javascript+XML sample files that ship with APP. That is the reference I use.
