So you may be wondering actually what is a server?(especially if you read What is active directory)
What is a server
Well a server is just a computer that serves information hence the name server. When you think of servers you may think of huge racks of whirring powerful machines in a server room giving thousands of people information, but that is not the only kind of server there is. Realistically any computer can be a server, it does not need any special server grade hardware or big fancy racks.
So what does a server do?
A server serves information or resourses to other computers(called clients), an example of this is the internet, all webpages and downloads come from a server(or many servers) somewhere that is serving you the webpage or download.
Different types of servers
There are many types of servers for many different applications some examples of these are:
Application server: these are a server dedicated to one application
Database server: A database server is used to run a database from they will usually have a raid configuration and fast hard drives so they can find data quickly
Fax server: A fax server is used to manage fax services
File server: A file server is a shared place for data to be stored and then accessed
Game server: A game server connects people together to play video games commonly used for online gaming
Home server: A home server is a server that is used for the home environment
Name server: A name sever also referred to as a DNS(domain name service) server provides domain name resolution.
Print server: Has printers installed on it to share through your network
Proxy server: A proxy server acts as an intermediary for a client and server.
Web server: A web server is used to host web pages and then serve it to clients upon request.