DOC is a file extension for word processing documents. It is associated mainly with Microsoft Word application. DOC files can also contain charts and tables, videos, images, sounds and diagrams. It supports almost all the Operating Systems.
is a format used in the MobiPocket Reader software on desktop and mobile platforms. Books in this format can have .prc and .mobi file extensions. MOBI was originally based on the PalmDOC format; adding HTML tags made it possible to create a high-compression version which compresses data to a high degree. There are a number of formatting restrictions – the text cannot be indented, and inserted tables and images cannot be formatted.