lrf The LRF format is a proprietary format developed by Sony in collaboration with Canon, as a document and text encoding standard for the Broad Band eBook file format. The format specifically targeted Sony portable eBook readers and was capable of encoding both text, pagination, and images. Being unencrypted, LRF encoded files do not enforce DRM. This is in contrast to the LRX format which is also part of the BBeB eBook file format which does support encryption for DRM files. The Sony eBook store announced in July 2010 a discontinuation of support for the LRF format in favor of the public and open EPUB format.
epub The ePub format is one of the many open source eBook file formats available. Initially released in 2007, it succeeded the legacy Open eBook format. The format was first defined by the Open eBook forum, part of the international digital publishing forum. EPUB digital books and publications all have the associated .epub extension and can be opened and viewed on any compatible device, software application, smartphone, or dedicated reader. The format is capable of optimizing the resolution of digital publications to suite the resolution of the device being used, making it inherently a 'reflowable' format.