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.
It is used as a common format for bitmaps in operating systems environments based on the UNIX kernel. It is designed for use in many types of graphics. It can be used for all kinds of data with two-dimensional arrays. It covers the RGB-space and transparency levels.