A server is a computer, or a running instance of an application, capable of responding client’s requests via client-server architecture. Servers can be formed by disc stations (mostly for home and office use), regular computers (tower servers), or professional server racks.
Servers are connected to other computers via network; they can be used by all the people on the network with a proper authorization (username and password) for sharing drives, printers, etc. The internet itself is also run by special kinds of servers, ensuring the availability of webpages and providing services such as DNS, e-mail, and others. Every server must of course be equipped with software specifically designed for it.
Home servers are perfect for sharing, backup, and managing documents in smaller networks as well as controlling the printer from various PCs (print servers). Generally, you can also access them from the internet. Professional business servers, on the other hand, require much more powerful hardware components, which ensure high stability, reliability, and overall problem-free performance.