Computer networking is the process of connecting computers and other devices so they can communicate and share information. A network may consist of only two computers connected together, or it may include thousands of devices spread across multiple locations. Networks are used in homes, businesses, schools, hospitals, government facilities, and nearly every modern organization.
A network allows connected devices to exchange data and access shared resources. For example, multiple computers in an office may use the same printer, access files stored on a central server, or connect to the internet through one router. Without a network, each computer would need its own separate equipment, files, and internet connection.
What Is a Network?
A network is a group of connected devices that can send and receive data. Devices may connect through physical cables, wireless signals, or a combination of both.
A small home network may include a wireless router, laptop, smartphone, smart television, printer, and gaming console. A business network may include hundreds of computers, servers, switches, wireless access points, security cameras, printers, and other devices.
The internet is the largest example of a network. It connects millions of smaller networks around the world and allows devices to communicate over long distances.
Why Networks Are Used
Networks are primarily used to make communication and resource sharing easier. Instead of keeping information on one isolated computer, a network allows authorized users and devices to access that information from different locations.
Common reasons for using a network include:
Sharing files and folders
Sharing printers and other hardware
Accessing the internet
Communicating through email, messaging, and video calls
Accessing websites and online services
Centrally managing users and devices
Backing up important information
Controlling access to company resources
Networks can also reduce costs. A business does not need to purchase a separate printer for every employee if multiple employees can use a shared network printer.
Networks also make administration easier. An IT technician may be able to install updates, manage user accounts, monitor devices, and troubleshoot systems from a central location.
Clients
A client is a device or software application that requests information or services from another device.
For example, when a user opens a web browser and visits a website, the browser acts as a client. It sends a request to the web server that hosts the website. The server processes the request and sends the website data back to the client.
Common client devices include:
Desktop computers
Laptops
Smartphones
Tablets
Gaming consoles
Smart televisions
Network printers
A client does not always have to be a physical device. Software can also act as a client. A web browser, email application, remote desktop program, and cloud storage application are all examples of client software.
Servers
A server is a computer or system that provides services, information, or resources to other devices on a network. The devices that request those services are called clients.
Servers are often more powerful than standard desktop computers because they may need to support many users at the same time. They may contain additional memory, storage, processing power, network connections, and backup components.
Common types of servers include:
File servers
Print servers
Web servers
Email servers
Database servers
Authentication servers
Backup servers
A file server stores documents and folders that users can access over the network. A print server manages print jobs and sends them to shared printers. A web server stores websites and delivers web pages to users.
Servers may be physical or virtual. A physical server is a dedicated hardware system. A virtual server is created through software and shares hardware resources with other virtual systems.
Client-Server Communication
In a client-server network, clients request services and servers respond to those requests.
For example, an employee may open a document stored on a company file server. The employee’s computer sends a request across the network. The file server confirms that the employee has permission to access the file and then sends the requested data back to the computer.
The general process is:
The client sends a request.
The request travels across the network.
The server receives and processes the request.
The server sends a response.
The client receives and displays the information.
This process can occur in a fraction of a second.
Nodes
A node is any device connected to a network that can send, receive, or forward data.
Computers and servers are nodes, but the term also includes many other devices. Routers, switches, wireless access points, printers, cameras, smartphones, and internet-connected appliances may all function as network nodes.
Each node has a specific role. Some nodes create and receive data, while others help move data toward its destination.
For example, a laptop may send a request to a website.