What is a server? Clients, servers and the services they run
In short: A server is a computer that provides a service to other devices, called clients. When you open a website, your browser is the client and a web server sends the page. Servers can sit in an office, in a data centre or in the cloud.
The simple idea
Most of what you do online is a conversation between two kinds of computer. A client asks for something, and a server provides it. Your phone's browser is a client; the computer that sends you the web page is a server. The words describe a role, not a special kind of box: any computer running server software can act as a server.
Common services servers provide
| Service | What it does | Everyday example |
|---|---|---|
| Web server | Sends web pages and app data | Opening a news website |
| Email server | Receives, stores and sends email | Your Outlook or Gmail inbox |
| File server | Stores shared files | The "S: drive" at work |
| DNS server | Turns names into IP addresses | See DNS explained |
| DHCP server | Gives devices their IP settings | See DHCP explained |
| Authentication server | Checks who you are | Signing in to a work account |
What makes a server different from a laptop?
Inside, a server has the same parts as any computer: processor, memory, storage and a network card. The differences are about reliability. Servers are built to run all day, every day, often with two power supplies, several disks that copy each other, remote management, and a rack-mounted case in a cooled room. Many servers have no screen at all: engineers manage them over the network.
Where servers live today
- On-site: in a cupboard or server room in the office.
- Data centre: a building full of racks with backup power, cooling and security, where companies rent space.
- The cloud: you rent servers, or just the services, from providers such as AWS, Microsoft Azure or Google Cloud. See what is cloud computing?
Most of these servers are now virtual machines: one physical machine runs many separate servers at once, as explained in virtualisation basics.
Real-world example: one click, many servers
You tap "buy" in a shopping app. Behind that one tap, a DNS server finds the shop's address, a web server receives your order, an authentication server confirms it is really you, a database server records the order, a payment server talks to your bank and an email server sends your receipt. Six or more servers, in different places, answer in under two seconds. When one of them fails, the whole purchase can fail, which is why companies watch their servers so closely.
Try this: in your browser, press F12, open the Network tab and reload a website. Every line is a request from your browser (the client) to a server. Count how many different servers one page uses.
Key takeaways
- A server provides a service; a client asks for it.
- Common services: web, email, file, DNS, DHCP and sign-in.
- Servers are built for reliability and are usually managed remotely.
- Servers live on-site, in data centres or in the cloud, mostly as virtual machines.
Original content written by Mohamed Fayas for FM TecHub. © 2026 FM TecHub. You're welcome to share a link to this page; please don't copy the text elsewhere without permission.