A wheel hub is the central part of a wheel that connects it to the vehicle's axle. It allows the wheel to rotate smoothly while supporting the weight of the vehicle. The hub typically contains bearings that reduce friction and enable easy movement. In addition to supporting the wheel, the hub also houses the brake components and may include features for attaching the wheel to the vehicle. Proper maintenance of the wheel hub is essential for safe driving, as a malfunction can lead to wheel misalignment or failure.