The C-Media AC97 Audio Device is a sound card driver designed for audio devices based on the AC97 audio codec standard, which was commonly used for integrated sound solutions in older computers. The driver allows your operating system (like Windows) to communicate with the audio hardware, enabling features like sound playback, microphone input, and more.

The AC97 (Advanced Component Architecture 97) was a widely used audio standard developed by Intel. It is a predecessor to more modern audio standards like HD Audio, but it is still used in some older computers.