Windows Services are an essential part of the Microsoft Windows operating system that runs in the background. They don’t have a user interface but they ensure core operating system features such as Web serving, file serving, event logging, error reporting, and printing. Windows services allow creating and managing long-running processes.
Windows services differ from the regular software that is launched by users and runs only when users are logged on. Windows services can be automatically started without the user intervention when the computer boots. They may continue to run long after the user has logged off and they can also be paused and restarted. Developers can develop Services by building applications installed as a Service.
Windows Services manage a wide range of functions such as data backup, speaker sound, network connections, display colors, and user credentials and perform functions similar to UNIX daemons
Windows Services are administered by a special utility provided by Windows – the Services Control Manager. Users can manage Windows Services via the Services Control Manager panel that presents a list of services and shows such details as the description of each service, its type, and the current status (running, paused or stopped). Users can start, pause, stop, delay start, or resume each service. Besides, users can perform many of these tasks when using the ServiceController class or in the Services node in Server Explorer.
Windows Services can be divided into three categories according to the specific actions and applications that they control: Network services, Local Services, and System. Some third-party applications, for example, antivirus software can also install their own services.
A user that has administrative privileges can delete services but that may result in the operating system instability. These procedures should be performed with caution and only when it is necessary.
The examples of Windows Services are DNS Client Service, Active Directory Service, Computer Browser Service, and Prefetch and Superfetch Service.
Developers can create Services in Visual Studio as .NET projects.
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