Xvid is a codec that compresses video files. Xvid files will play on many DVD or Blu-ray players and Windows 10 or later by default.

I have some Xvid .avi files which have actual interesting video in a 16:9 aspect ratio, but the files themselves have black rectangles at the top and bottom to letterbox into a 4:3 video frame. I ...

If you want to play QuickTime Video format DivX, XviD, MOV files in Windows 11/10, you can install QuickTime or any of these other media player software.

I'm confused about some aspects of Xvid and file containers. If i am to understand correctly, xvid and divx are mpeg4. So why is it not possible to stuff a xvid file with acc in an MP4 container ...

A new iPad app, CineXPlayer, allows you to watch videos encoded using the Xvid format. You can even easily transfer the files using iTunes's File Sharing features.