Plucker is an Open Source free mobile and desktop e-book reader application with its own associated file format and software to automatically generate Plucker files from text, PDF, HTML, or other document format files, web sites or RSS feeds. The format is public and well-documented. Free readers are available for all kinds of desktop computers and many PDAs. PDB is a container format for record databases in Palm OS, Garnet OS and Access Linux Platform. Its structure is similar to PRC resource databases. The PalmDOC eBook format is a special version of the PDB format.
FictionBook is a popular XML-based e-book format, supported by free readers such as FBReader, Okular, CoolReader, Bebook and STDU Viewer. The FictionBook format does not specify the appearance of a document; instead, it describes its structure and semantics. All the ebook metadata, such as the author name, title, and publisher, is also present in the ebook file. Hence the format is convenient for automatic processing, indexing, and ebook collection management. This also is convenient to store books in it for later automatic conversion into other formats.