OGV is a video file format that uses an open OGG container. The name of the format is also associated with this - an abbreviation for Ogg Video File. The developer of both formats is Xiph.Org. The OGV format stores video streams that use either one or several different codecs (for example, Theora). OGV files can be played on almost any media player. They are also used when displaying web pages using HTML5, however, these files (even videos) often have the .OGG extension. OGV video compression is lossy.
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.