ePub is now a standard e-book file format that is supported by almost* every e-book reading device include Sony Reader, BeBook, IREX Reader, iPhone and the upcoming Nook from Barnes & Noble’s.
Other than hardware devices, you can also read .epub books on your desktop or mobile phone using free e-reader software like Stanza, Mobipocket, FBReader (for Linux), Aldiko (for Android) or Adobe Digital Editions.
[*] Amazon Kindle uses a proprietary format (AZW) and cannot read ePub files directly though you can use the free Stanza desktop application to convert an ePub ebook into AZW (or even PDF), a format that your Kindle can understand.
Download Books in ePub Format
O’Reilly, Shortcovers, Sony Store are some popular book publishers that provide ebooks in ePub format but if you are looking to download classic titles to read offline, the best place is Google Books (select the “public domain only” option).
Google Books has more than a million public domain (out of copyright) books in the EPUB format that are completely free and they aren’t protected by DRM so you can rea