Thanks everyone for the information.
I assume the "kePub" is what I would get if I bought from Kobo.
Right now I just plan to use it for library books (already have a Kindle),
but who knows in the future?!
I have read (a post above and other places) that the Kobo desktop is very problematic. My Kobo is working just fine downloading from the library, maybe I shouldn't tempt fate and get into the desktop app (or the Borders one). I really just got it for the library anyway (have a Kindle for purchases, easy on Amazon). I thought I would need a desktop app to delete books from the Kobo, but found out how to do it (one by one unfortunately) from the device.