Extension: avi
What is it? Audio Video Interleave File
Where’s it from? Avi is an old, widely used standard for audio/video files. Avi files are uncompressed, so they take up more disk space and take longer to download than compressed files such as MP3. However, the quality of avi files is higher than compressed formats.
How do I use it? Virtually every program that plays audio/video files will play avi files, including Windows Media Player and Apple Quicktime.
Can I safely delete or move it? Yes.
Can it be dangerous? Yes. Avi files found on P2P networks such as Limewire are often infected with malware. Use antivirus software.
— David Hakala