Okay, to keep this basic, there are three major types of publishers in publishing, and I don't see this model changing at all. (deanwesleysmith.com)
It's always helpful to read others experience, and reasons to go with what type of publisher. (hubpages.com)
You have questions about publishing a book — how to do it, where to publish it, what mechanisms to use... what are the different types of publishers? (womeninpublishingsummit.com)