What Is a Server? Understanding the Role of Computer Servers

Servers are the life force of any computer network. They provide email, web services, and other shared resources that users need. For these reasons, IT professionals must oversee a company's computer server daily to make sure it works properly. In this article, learn what a server is, how it works, the different types available, and its role in computer networks.

What is a server?

A server is a dedicated computer that provides functionality or data on behalf of other devices, often called clients. This architecture is known as the client-server model. An ordinary desktop computer can function as a server in a data center as long as it can listen to requests from clients.

The term also refers to a computer program that provides functionality for other programs. Consider, for example, a web server that delivers webpages over the Internet through a client, like a web browser. However, in most cases, the term refers to a computer rather than a program.

Servers are essentially machines where multiple clients connect to access resources, either over a local area network (LAN) or a wide area network (WAN). They provide a variety of functionalities referred to as services. These services could range from accessing data and retrieving a website to processing emails.

Servers in a computer room

You can set up a dedicated server to handle each of these services as well as a centralized server to assist each of these services on the same device. Which you will likely prefer depends on the size of your organization.

A single device has the capability to handle requests and provide services to multiple clients. Clients can interact with the same one simultaneously. On the other hand, a single client can connect to and use services from multiple. This scenario is very common in distributed systems where different servers offer specific functions.

Servers form the backbone of computer networks. They allow for centralized management of resources while enabling data sharing, collaboration, and access across devices.

What's the purpose of a server?

Each server has a specific role within a networked environment. The main goal of any one of these devices, however, is to compute, store, and manage data within a network. They also provide a way to protect data. Their core functions include:

  • Resource sharing. Servers enable sharing of resources such as files, applications, and printers among multiple clients on a network.
  • Data storage. Servers store and manage data, working as repositories for information authorized users or applications can access.
  • Computation. They can perform computations on behalf of clients, offloading processing demands from individual devices.
  • Communication facilitation. They act as a gateway between different computers within a network, allowing communication between them and sometimes even bridging gaps like middleware.

When you connect, you can access files, programs, and any other information you need. In essence, servers exist to provide services.

How does a server work?

Clients access services provided by servers through networks. We now know that a server is a computer system that accepts requests for online files and transmits those files to the client. Therefore, to act as a server, a computer system should be able to receive requests from a client via a network connection thanks to the client-server model.

When the client wants information from a relevant server, it sends a request. The server listens for incoming requests on a designated port. It finally sends this response back to the client over the network. Most servers have to perform multiple tasks on a single request, such as identifying and authenticating the requested client.

For example, you access a web server when you surf the web. This starts when you type the URL into your browser. The client, which is your browser, sends a request to the server hosting the desired site. It then employs domain name system resolution to translate domain names to IP addresses.

The server processes the request, possibly fetching data from a database. Once processed, the server compiles the webpage and sends it back as a response to your browser. Your browser then interprets the received information, rendering the page for you to view.

Key features of a server

Servers can differ in terms of capabilities or reach, but all should share the following key features.

  • Scalability. Servers can run multiple programs and handle multiple users accessing it simultaneously.
  • Centralization. They allow for centralized data storage and access, increasing efficiency, security, and management.
  • Security. Servers are more secure than standard desktop computers because they can be equipped with advanced security features, such as firewalls and intrusion prevention systems.
  • Quality performance. These devices have the design to handle heavy workloads and can handle a high volume of requests.

Physical servers vs. virtual servers

Servers can be categorized into two main types: physical servers and virtual servers. A physical server is a tangible machine used to run server software. Here, the software is a set of programs installed on a server to enable it to perform specific tasks.

Physical servers use a traditional processor and RAM. Each physical device operates independently and runs a single operating system. They work best for tasks that require high computational power. A vast majority of physical servers are found in data centers.

A virtual server, also known as a virtual machine, is simply a virtual representation of a physical server. They use a hypervisor to divide physical servers into multiple servers.

A hypervisor refers to a software component installed to act as the bridge between the physical hardware and the virtual machines. It partitions the physical device's resources, such as CPU, memory, and storage, and allocates them to individual virtual machines.

Virtualization technology is what allows a single physical server to host multiple virtual servers. Like a physical server, each virtual server has its own operating system and applications.

Most servers in businesses and cloud computing are virtual servers.

Components of a server

A server consists of several components that work together to ensure smooth operation. It has necessary hardware and software to provide services to clients.

Processor (CPU)

The central processing unit (CPU) is critical to the device's performance. The CPU determines its capability to handle multiple requests simultaneously. Servers operate with high CPU-intensive software; therefore, they require a powerful processor to keep up with demands.

Memory (RAM)

Memory, or RAM, stores data that the device needs to access quickly. The RAM helps the CPU keep up with the workload. The amount of RAM depends on the device's expected capacity and workload. For instance, a server running multiple applications simultaneously would require more RAM than one running only a few applications.

Storage devices

Servers require a large amount of storage to store data. This can be in the form of hard disk drives (HDDs) or solid state drives (SSDs). The storage capacity of a server can vary depending on the needs of the network.

RAID controllers

A RAID (redundant array of independent disks) increases the reliability of a server's hard drive. RAID is a data storage technology that allows multiple hard drives to work together effectively. The technology ensures that if one hard drive fails, the data stored in it would be recovered from another functioning hard drive. This redundancy protects the server's data from potential hardware failures.

Network interface card (NIC)

The network interface card enables communication between the server and the network. NIC connects the server to the network and enables it to communicate with other devices. This hardware device also provides high-speed connectivity to other connected devices, such as switches.

Power supply

The power supply provides the necessary electrical power to the server. The power supply unit (PSU) regulates the incoming electrical voltage to provide a consistent power source for the device's components.

Network connection

These devices are connected to a network, either a LAN or a WAN or the Internet, through network interfaces. Internet connection is what enables them to communicate with other devices.

Cooling system

Servers generate a lot of heat during their high processing power. A cooling system, such as fans or liquid cooling, keeps the device components at optimal temperatures.


The software includes operating systems. Before a computer server can perform any given function, it needs a reliable operating system (OS). A physical server runs an operating system, such as Linux or Windows servers, among others.

Windows servers are the most common operating system used for enterprises. They are a product of Microsoft Corporation and offer a range of features to support several services. They have easy integration with other Microsoft products, a user-friendly interface, and offer support for popular programming languages. However, the downside to using a Windows server is that it requires more memory and is prone to security threats.

Linux servers are also a common operating system used. Linux is an open-source operating system that operates on various hardware platforms. It's particularly popular with large organizations because it's free, stable, secure, and customizable.

The OS is also renowned for its command-line interface (CLI), which gives users better control over their systems. Popular versions of Linux included on computer servers include Red Hat Enterprise Linux and CentOS.

Types of servers

There are different types of computer servers out there designed to meet specific needs. The following are the most common ones used today.

  • File servers, which are responsible for storing and managing files, allowing users to access and share them over the network.
  • Web servers, which host websites and deliver web pages to users when they request them through a web browser.
  • Database servers, which store and manage large amounts of data, allowing users to retrieve and manipulate the data using database management systems.
  • Mail servers, which handle the sending, receiving, and storage of emails, enabling users to send and receive messages over the Internet.
  • Application servers, which provide a platform for running and managing applications, allowing users to access and use them remotely.
  • DNS servers, which translate domain names into IP addresses, enabling users to access websites and other resources using easy-to-remember names.
  • Print servers, which manage and control printing resources, allowing users to send print jobs to printers connected to the network.

Frequently asked questions

Why are servers always on?

The main function of these devices is to deliver services that are constantly required. If a server goes down or fails, then it can jeopardize business operations. Servers need to be reliable and build with the right resources, like enough storage devices, high computing RAM, and quality CPUs.

These devices and their components must be set in a redundant fashion. That means that if one component fails, it shouldn't impact the whole network.

Is there a difference between a desktop computer and a server?

While each has a distinct purpose by design, the underlying hardware components form the foundational similarity between desktop computers and servers. Both rely on components such as memory, storage, and networking components to fulfill their functions.

However, a desktop computer typically comes in compact form factors suitable for individuals. Servers, on the other hand, feature various form factors to accommodate diverse infrastructure requirements.

Where should you store a server?

It should be stored in a room that is well-ventilated with controlled temperature, access restrictions, and backup power.

Who is responsible for maintaining servers?

System administrators or IT professionals typically manage servers. This is because they require specialized knowledge for setup, configuration, security, monitoring, and maintenance.

Can my computer be a server?

Yes. Any computer, desktop, or laptop can be one with the right software. Keep in mind that a computer and the related software must not be turned off in order to be accessible.