This is an old revision of the document!
Hardware Servers can vary widely from personal computers to specially built rack mounted computers.
Hardware requirement for servers vary widely, depending on the server's purpose and its software. Servers are more often than not, more powerful and expensive than the clients that connect to them.
Since servers are usually accessed over a network, many run unattended without a computer monitor or input device, audio hardware and USB interfaces. Many servers do not have a graphical user interface (GUI). They are configured and managed remotely. Remote management can be conducted via various methods including Microsoft Management Console (MMC), PowerShell, SSH and browser-based out-of-band management systems such as Dell's iDRAC or HP's iLo.