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.
ALAC is the format of a small specialized program called an audio codec. Its main task is to compress a file with digital music without losing its quality. The name of the format created by Apple's IT giant is Apple's abbreviation Lossless Audio Codec. This format may also be called ALE (from Apple Lossless Encoder). Files in this format can play devices even with limited computing resources - such as an iPod. When compressing a file in this format, it is approximately 40-60% of the original file. Now almost every multimedia player based on the libavcodec library is able to play ALAC format files.