Adding pagination to nodes I'm using Drupal 7, CKEditor (not wysiwyg module). By default the nodes are not paginated but the client wants to have nodes of certain content-type to be paginated. And wants control of this pagination i.e. set page breaks.

How can I make the nodes to paged? And how can I control it? 

P.S. I cannot find any  useful explanation (tutorial) of how drupal pager works, so if you know any, it's highly appreciated to post it here.
It is incredibly easy. Use BOOK content type. Just need to enable Books in core modules. If you already have lots of existing content (to much to copy/paste into book pages), you could add a field for Node Reference and link the pages that way.  Book has all that "pagination" functionality -- as well as local menu/index -- built in. Great solution if you aren't too far along.  At the very least, enable Book module and do a sample to demo for client -- to help you conceive the exact behavior that you want.

By the way, that approach is independent of your WYSIWYG (CKEditor).