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.
A file with the DOCM file extension is a Word Open XML Macro-Enabled Document file used in Microsoft Word. It was introduced in Microsoft Office 2007. DOCM files are just like DOCX files except that they can execute macros, which lets you automate repetitive tasks in Word.