When you're looking for an assigned reading in a book, or need to cite some information that you found, page numbers are the obvious way to mark the spot.
Many ebooks, especially those in PDF format, retain their original pagination...so check the top and bottom of each page for numbers as you read. You can also usually find chapter page numbers by looking in thetable of contents (within the first few pages of the book).
But, there are some ebook formats that do not display page numbers. In books like these, you may need to search inside the book to find a chapter/section title, or a particular word or phrase. Or, again, use the table of contents.
EBSCOhost's EPUB format is one example of an ebook format that does not display page numbers. It may help if you sign up for a free MyEBSCOhost account, which will let you keep the book in your folder for easy access (or even download it). You can thenadd notes to the sections that you need to get back to quickly.