What is a server? An overview in 500 words or less



‘Server’ is one of those computer-jargon words you think you understand until you’re asked to explain it.

Put on the spot, many people can’t provide an accurate technical definition of servers. What do they do? What are the different types?

So, let’s clarify. What is a server, exactly? Here’s an overview in 500 words or less.


What is a server?

Outside of computing, a server is someone that serves you. For example, by taking your request for food in a restaurant, and bringing that food out to you.

Well, a server in computing does the same kind of thing. But with websites, or data, or programs, or other resources that you access through the computer, over a network.

Any computer can act as a server, provided it has the right software to receive and respond to requests. However, this isn’t always the best way. Built-for-purpose server hardware is better suited to serving reliably.

So, what is a server? It’s a type of computer that provides data to other computers.


How do they work?

A server accepts and responds to requests you, or your software, (known as ‘the client’) make over a network. So, for instance, if you request a specific webpage, that request goes to a server which then delivers (or serves) that webpage to you.

Servers must stay switched on all the time. (Which is why they’re designed to run continuously.) So, this high availability means you can make a request at any time, and the server will be active and able to deliver the data requested.

One server can serve multiple clients, and one client can request from multiple servers at once.


Different types of server

Another way of looking at the ‘what is a server’ question is to examine the different types of server. (And there are many.) Here are a few examples.

·       Proxy server

A proxy server acts as a middleman between a client and another server. Responses can come from the proxy server cache. Or, if the requested information isn’t cached, the server will send the request to the correct server, and then send the response back to the client.

·       Cloud server

A cloud server is a virtual server rather than a physical one. You access it remotely via the internet, and it’s delivered entirely via a cloud computing platform.

·       Mail server

A mail server is where emails get stored and sorted. When you check your emails, you request them from the mail server.

·       Web server

Web servers serve requested HTML pages and files. When requesting a webpage, your browser acts as the client to a web server.

·       Database server

Database servers are used to access and retrieve data from a database.


Computer servers

A server is essentially the middleman in a call and response game. A client sends a request to the server, which performs an action and sends a response back.

They’re used for all sorts of fundamental tech legwork, from serving your emails, to responding with websites, to retrieving data.


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