| Platform SDK: DLLs, Processes, and Threads |
Microsoft® Windows NT®/Windows® 2000 supports an application type known as a service. A service application conforms to the interface rules of the Service Control Manager (SCM). It can be started automatically at system boot, by a user through the Services control panel applet, or by an application that uses the service functions included in the Microsoft® Win32® application programming interface (API). Services can execute even when no user is logged on to the system.
Windows NT/Windows 2000 also supports a driver service, which conforms to the device driver protocols for Windows NT/Windows 2000. It is similar to the service application, but it does not interact with the SCM. For simplicity, the term service refers to a service application in this overview.
Note Windows 95 and Windows 98 support a subset of the functionality provided by the SCM. For more information, see Windows 95/98 Service Control Manager.