In a client-server architecture, the server provides a variety of services to the client. The server often stores data or files. Servers typically possess more computing power than clients. Services are also optimized for simultaneous multiuser access over a network.
The term server may refer to a specific physical device. More precisely, though, any networked application that listens on a port and binds a TCP/IP socket is a server. So any given device (including an end user PC) that accepts network requests for data or services is acting as a server. It is not unusual for multiple servers in this sense to be hosted on the same device. Likewise, with respect to physical provisioning, servers are often configured in clusters or virtual teams, in which many server platforms or products run in parallel.
The term server, therefore, is probably best understood in the logical sense as a network-sensitive process. Various types of physical hardware be may adapted to optimize the performance of such servers, depending on the load, the desired latency, the number of simultaneous connections, and other application characteristics.
For Windows Server products, various services (in the business sense) are called roles performed by the server. Examples of such roles include:
The term term service has a technical meaning in Windows. In Windows, a service is a long-running utility process (similar to daemon in Linux or Unix). To distinguish the different uses of service and to show these uses related to the idea of server, here are some example statements: