Ogg is a relatively young format of modern audio formats, which is consistently among the three most popular and competes worthy with MP3. This format (full name Ogg Audio File) appeared in 2002, was developed by the nonprofit organization Xiph.Org Foundation, is free and free. Ogg files are very convenient for storing data, because they have a high degree of compression. For users, Ogg is attractive precisely for this, as well as high quality sound. It is also attractive because it is an effective alternative to paid audio formats. You can listen to these files in Winamp, AIMP, VLC, XMMS software players.
M4R is a highly specialized audio file format. This format (full name - iPhone Ringtone File) was developed by Apple's IT giant specifically for the iPhone. This format creates music ringtones for the iPhone. ITunes Ringtone is the main program for opening files with the extension .m4r, and their creation is mainly using Apple iTunes. Formally, M4R files can only be created from songs and other works purchased in the iTunes music store. The size of the created ringtone in the M4R format can be a maximum length of not more than 40 seconds.