is a format developed by the International Digital Publishing Forum. It is characterized by the XML- and XHTM-based optional use of CSS styling. The main feature of this format is the use of reflowable text (word wrap) which makes it possible to adapt the image to different device displays. The ePub file is a zip-archive with an .epub extension.
this is a new format that supports lossless and loss compression quality for images on the Internet. The Google Company developed this format specifically to do work online as quickly and conveniently as possible. The main advantage is that its file size is small compared to other image formats, but similar in image quality.