The document compares two Sony camcorders, the HDR-XR500V and HDR-XR520V. Both camcorders have the same dimensions and sensor, but the HDR-XR520V has a larger 240GB hard drive compared to the 120GB in the HDR-XR500V, allowing it to record more hours of footage. Both camcorders also have the same core features like 12x optical zoom, touchscreen display, and compatibility with Memory Stick media. The main differences are in storage capacity and battery life.