What is my Adobe ID?

Hello Adobe Community, 

        I've recently set up an Adobe ID account in order to borrow and read books from my digital library.  Yet when I try to authorize my computer with Adobe Digital Editions it asks for my Adobe ID, and I don't know what that ID is.  I've searched through all my profile information and cannot find anything that indicates what my Adobe ID actually is. 

       Has anyone else had this problem?  Can anyone help?  Thank you kindly!