What is... A server

A guide to servers

Author:  Tina Landers

A server is often believed or imagined to be a large and/or powerful computer. That's not entirely correct. While some servers may be large, it's not their size that designates them as servers. In fact, an appropriately configured PC can be a server. A Server is a computer that runs a server Operating System and server applications (Programs).

There are many types of server, usually named after the service or function they provide or perform. Some server types are Web Servers, Print Servers and Email Servers.

Server computers are generally configured differently from other computers. Depending on its purpose (ie the applications or programs that it will run), a server is often configured with various forms of redundancy built-in. For example, it may have multiple Hard Disk Drives configured to continue working as one even if one of the multiple failed, it may dual power supplies for the same reason. Consider an Email Server in a large company - it must have redundancy built-in to ensure it keeps working 24/7. After all, its job is to send, receive and store all of the company's email - between employees as well as to and from external parties. If it stopped working, a significant part of the company's communication system becomes incapacitated. A Print Server would generally be configured with more RAM and less Hard Disk Drive space - its job is to manage the queues of information sent to one or more printers in the company.

A server's operating system looks and functions differently to that of our home computer's. Because it's generally run and managed by a technically minded Administrator, it doesn't need or have any extra "good looks" (the graphics that are designed to simplify the computer experience for people like you and me). Removing all those extras makes it a "leaner and meaner" machine. Additionally, where your home computer is built to satisfy the needs of one user with one request at a time, a server is built and configured to meet the needs of multiple users (called "Clients") with multiple requests at any given time. 

Server operating systems and applications can also be configured so that multiple computers can be configured to work together as a server, ie. to the end-user, those multiple computers look like a single server. The applcation/s (or program/s) function as one across the multiple computers. There is a significant amount of flexibility in configuring a server.

A server is generally not visible to the end-user that it services, ie. at work you may send a document to the printer and collect it when it has printed. You wouldn't know that the document was actually sent to a server which queued it for printing so as not to conflict with someone else's document/s. Likewise, you've likely reached this Web Page by being passed through many servers along the way.

and here's a home network print server