The Microsoft LifeCam Rear driver refers to the driver software required for Microsoft LifeCam webcams, specifically for the rear-facing cameras used on some laptops, tablets, or Windows-based devices. LifeCam is a brand of webcams produced by Microsoft, and while most LifeCams are external devices that connect via USB, some Windows devices (particularly laptops and tablets) come with built-in cameras, including rear-facing cameras, that are often branded under the "LifeCam" name.

In essence, Microsoft LifeCam Rear could refer to the driver for the rear-facing camera on a Microsoft device (like a Surface tablet or a laptop with a built-in rear camera) that uses LifeCam technology for video and camera-related functions.