EPUB - Wikipedia, the free encyclopedia | The 21st Century | Scoop.it
From en.wikipedia.org - May 13, 2012 8:16 PM

EPUB (short for electronic publication; alternatively capitalized as ePub, ePUB, EPub, or epub, with "EPUB" preferred by the vendor) is a free and open e-book standard by the International Digital Publishing Forum (IDPF). Files have the extension .epub.