Back in the day, this was a common way to distribute Windows 95, especially before widespread internet access and USB drives made it easier to share and install operating systems.
You're interested in learning about a classic piece of computing history! windows 95 c.img file download
The .img file you're referring to is likely related to the installation process of Windows 95. Specifically, I think you might be interested in the WIN95 IMG file, which is a CD image file. Back in the day, this was a common