Generally, any hardware component that can be driven by software.
In Microsoft Windows 2000, you can work with devices using the Device Manager, which you access through the System utility in Control Panel. In Windows NT, you can view, stop, and start devices using the Devices utility in Control Panel.
In Microsoft SQL Server version 6, a device is a file used to store SQL Server databases. Multiple SQL Server databases can be stored on a single device, and a single database can span multiple devices.
The master system device contains four databases: