This article explains three file formats that use the VOB file extension. It also explains how to open each type.
How to Convert VOB TO MP4 | Tutorial (2022)
A file with the .VOB extension is most likely a DVD-Video Object file, which can contain both video and audio data, as well as other movie-related content such as subtitles and menus. They are sometimes encoded and are normally stored in the root of a DVD in the VIDEO_TS folder.
3D models/objects created with the E-on Vue 3D modeling program also use this file extension. They can be textured using the information stored in a MAT (Vue Material) file.
The Live for Speed car racing video game also uses VOB files to texture and model 3D cars. The vehicles are symmetrical, so only half of the model is in the file and the rest is generated by the game.