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.
AU is an audio file format created in Audacity. This is a free cross-platform program designed to edit audio files. AU format (Audio Units) was developed by Sun Microsystems. This format greatly simplifies the task of reliable storage of audio files. An AU file consists of 3 parts: a header (max. 24 bytes), a description block of various sizes, and audio data. The file format is used on computers running the Sun or Unix operating system. However, it opens with other audio players. The AU format uses the logarithmic encoding method, previously very popular on computers running the Sun SPARCstation operating system. Previous sound file formats, in order to reduce the size, used the logarithmic scale of recording samples. Among the representatives of such formats, the Sun AU group of formats, which are still in action, gained great fame. Problems with opening the AU file usually manifest themselves when there are no corresponding applications that would be installed on the PC. Applications that use .AU files are Apple QuickTime Player, Microsoft Windows Media Player, Real Player, Winamp, and other widely used audio players. And this is the vast majority of professional audio editors.