DAT file is a file format written to save sounds, midi, wave, pallets, images, and levels. In short, this file format contains vital information for specific software, and the data is usually in either binary or plain text. In rare cases, DAT files may include a video file. DAT files are opened using text editors like Notepad++ and TextEdit.
AC3 is an audio format designed by Dolby Digital to offer surround sound listening. This format is available on most Blu-ray and DVD media files and is played using a Dolby Digital DVD Player. Interestingly, AC3 can be output in up to six speakers of a home stereo system. On a computer, AC3 can be opened on VLC Media Player, Apple QuickTime Player, and Windows Media Player.
VLC Media Player Apple QuickTime Player Windows Media Player