LRF - Sony Portable Reader File operates as a proprietary format that is native to Sony’s line of e-readers. LRF files contain data, including images, text and pagination data, for Sony BroadBand eBooks. LRF files are just one of two BBeB book formats that are available for use. Using LRF files is relatively simple, provided one has a Sony e-reader to open and use these files with. There are a number of third-party programs available that are capable of opening and modifying LRF files, including Canon’s Book Creator and the freeware Makelrf and LRFParser programs.