The ABW file format is the default document format for the AbiWord word processing software and the format is based on XML. The ABW file format allows for advanced document layouts, rich text formatting, lists, tables, images and footnotes. ABW files are similar in nature to Microsoft Word DOC files, however, unlike Microsoft Word files, the AbiWord program can run on almost any computer operating system.
was developed for the first mass-produced e-book reader – Rocket eBook. The format is written in Ruby. RB files are containers holding the entire content for a Rocket eBook device. It has DRM protection capability which is not used in the books published at present due to the format’s lack of popularity.