Sony is one of the founding members of the Blu-Ray Disc Association (BDA) and one of the main developers of the Blu-Ray Disc format. Tape 4 Backup offers BDs by Sony with 25 GB capacity available in write once and rewritable forms as well as 50 GB dual layer Blu-Ray Discs in write once form. Blu-Ray DVDs are expected to replace common DVDs as the new standard and are already being used to present High Definition (HD) movies by Warner Brothers, Lions Gate Studios, Twentieth Century Fox, Walt-Disney, MGM (Metro Goldwyn Myer) and some smaller companies like Paramount, etc. The Sony PS3 is also a Blu-Ray Disc player and can be used to play games, music and movies on Blu-Ray Discs. Imation, TDK and Verbatim BDs (Blu-ray Discs) are also available in both 25 GB and 50 GB capacities.