View full size image. Measured by surface area, the Caspian Sea is the world's largest inland water body. The sea covers roughly 143,200 square miles (371,000 square kilometers) and borders five countries: Iran, Russia, Kazakhstan, Turkmenistan and Azerbaijan.
A logical device driver is a high level abstraction of how a device behaves. A physical device driver is a driver for a specific piece of hardware. The logical device driver talks to the physical device driver for you to keep you abstracted from the underlying hardware. For example, there are many different types of printers, and they typically come with their own drivers.
The drivers in the USB 2.0 driver stack ship in Windows XP with SP1 and later versions of the Windows operating system. The USB 2.0 driver stack is designed to facilitate high-speed USB devices as defined in the USB 2.0 specification. At the bottom of the USB driver stack is the host controller driver.