Sony Portable Reader File (.lrf)
The LRF (Sony Portable Reader File) is a proprietary eBook format developed by Sony for its eReaders, such as the Sony Reader. It stores eBooks and textual content in a compressed binary format, including text, images, and pagination data. Introduced as part of the Broad Band eBook (BBeB) family, LRF files are unencrypted, whereas their encrypted counterparts use the LRX extension. The format became obsolete in 2010 when Sony transitioned to the EPUB format. Despite its obsolescence, LRF files can still be opened and converted using various software tools.