Server

A server is a robust computer or software on a computer that delivers services to other computer programs and their users. These services include storing, processing, and managing data, devices, and systems. In a data centre, the physical computer running a server program is often called a server.

Servers are the backbone of organisations, providing network devices and systems with the necessary resources. They offer businesses essential scalability and efficiency.

Servers can handle intensive workloads beyond a traditional computer's capabilities. Whether it's hosting a website with a large amount of data, setting up a shared drive for a department, or managing thousands of queries per minute, servers are crucial for processing and hosting demanding workloads.

How do servers work?

As previously mentioned, a server can be either a physical computer or software on a physical computer. To function as a server, a device must be configured to listen to client requests on a network connection.

When a user, also known as a client, needs data or functionality from a server, they send a request over the network. The server receives this request and responds with the appropriate information. This is known as the request-and-response model of client-server networking or the call-and-response model.

In addition to fulfilling the client's request, a server often performs many other tasks, such as verifying the requester's identity, ensuring that the client has permission to access the requested data or resources, and correctly formatting or returning the response in a certain way.

Types of servers

There are many different types of servers, often categorised by their tasks.

Application servers

Application servers run – you guessed it – applications instead of local applications on client computers. Applications that require a lot of resources and are shared by many users are often run on application servers. Examples of application servers include:

DNS servers

DNS servers (Domain Name System) are application servers that convert human-readable names to IP addresses that client computers can read. The DNS system is an extensive database of names and other DNS servers, each of which can be used to look up an otherwise unknown computer name.

Mail servers

Mail servers are a well-known type of application server. Mail servers receive emails sent to a user and store them until a client on behalf of that user requests them.

Database servers

Database servers store a lot of data for organisations. Databases must be accessible to multiple clients at anytime and may require extraordinary amounts of disk space.

An organisation no longer must provide this themselves thanks to the cloud. AWS, Google Cloud, and Microsoft Azure allow organisations to store their data in the cloud.

File servers

File servers store and distribute files. Multiple clients or users can share files stored on a server. Additionally, files can be more easily stored centrally for backup or fault tolerance than trying to ensure the security and integrity of files on every device in an organisation.

Print servers

Print servers enable the management and distribution of print functionality. Instead of connecting a printer to every desk, a single print server can respond to print requests from different clients.

Proxy servers

A proxy server acts as an intermediary between a client and a server. A proxy server is often used to isolate clients or servers for security purposes. A server responds to the proxy server, which then responds to the client. The proxy server receives the response from the second server and then responds to the original client as if it were responding to itself.

Web servers

One of the most common types of servers is a web server. A web server is a special application server that hosts programs and data that users request via the Internet. Web servers respond to requests from browsers on client computers for web pages or other web-based services.