You can open .DAT files that contain text, with text editors, like Notepad, Notepad++, VS Code, etc. But it is not possible to know what contains in a DAT file.

Sometimes it’s difficult to tell what the DAT file is about unless it is created by some software that users know. DAT file contains text, videos, config, or pictures related data, so opening the file ...

If the file contains multimedia data, you can try opening it with a media player such as VLC. If the file contains program data, you may need to use a specialized application or text editor to open it ...

Convert DAT File to AVI using the simplest ways mentioned in this comprehensive article. They are very simple to execute and has no super science in it.