ePub is short for electronic publication. It is one of the most popular e-publication sharing formats along with PDF. ePub files use the ".epub" file extension.
EPUB is a technical standard published by the International Digital Publishing Forum (IDPF). It became an official standard of the IDPF in September 2007.
In order to open or read the .epub format files, you will need an ePub reader.
You can download Calibre ebook reader for accessing ePub files on Linux.