Compatibility of media player refers to the ability of a media player to play media files that have different formats and codecs. Formats are the ways that media files are stored and organized, such as MP3, MP4, AVI, etc. Codecs are the ways that media files are compressed and encoded, such as H.264, AAC, DivX, etc. Different formats and codecs have different advantages and disadvantages, such as quality, size, speed, etc. Therefore, some media players can play some formats and codecs better than others, or some media players can play some formats and codecs that others cannot. For example, VLC is a media player that can play almost any format and codec, while Windows Media Player can only play some common formats and codecs. Therefore, VLC has a higher compatibility than Windows Media Player. Compatibility of media player is an important factor to consider when choosing a media player, because it can affect the quality and availability of the media files that you want to play.