DivX is a package that includes all the DivX codec, player, utilities, and documentation that you need to play DivX files. DivX codec is based on the MPEG-4 compression standard. This codec can reduce an MPEG-2 video (DVD format) to ten percent of its original size. DivX is a digital video compression technology based on the ISO MPEG-4 standard. Read more... All the changes in the Version 5.05"b" are integrated in the new DivX Player 2.1. There is also no changelog to say what is new or fixed in this player build. Also for download available is the first Version 5.0.6 for MacOS. Don´t be frustraded if you don´t find a version 5.0.5b on their site. they just replaced the 5.0.5 download with the new file without any notification. A hint is that the file, after they had been updated, is 1mb bigger then the original version. So just download it. DivX Homepage