Chapter 1 · Computer Networks
1.1Introduction to Computer Networks
What a computer network is, what it connects, what moves across it, and where we use networks every day.
Written and checked by Muhammad Raheel(opens in a new tab)
Full Stack Developer · AI Engineer · Reviewed 21 Oct 2026 · 2 min read
On this page
Think about your phone, the computer at school and the printer in an office. On their own, each device works alone. Join them together and they can talk, share and help each other. That joining is what a computer network does. This topic opens Chapter 1, so it starts with the basic idea that the rest of the chapter builds on.
What is a computer network?
Why does this matter? A network lets people share information quickly and easily. It saves time and effort, because you do not have to carry files from one machine to another. The book points out that networks are used in homes, schools, offices and businesses, and that modern life depends heavily on them for daily tasks.
What a network connects
A network is not only for computers. The book lists computers, mobile phones, printers and other digital devices. Figure 1.1 in the book, "A computer network connects multiple devices to share data and resources", shows a router in the middle with a computer, a laptop, a monitor, a printer and a phone around it.
The devices talk in two ways:
- through cables (wires that join the devices), or
- through wireless signals (Wi-Fi, with no wire at all).
What travels between them? The book says data, files and resources move from one device to another. A "resource" is something many people can use, like one shared printer.
Networks also come in different sizes. A network can be small or large, depending on the need. Two phones sharing a hotspot form a tiny network. Topic 1.3 shows much bigger ones.
Uses of Computer Network
The book gives six everyday uses. Learn them, because "Write two uses of computer networks" is an exercise question.
| Who or what | How it uses a network |
|---|---|
| Internet browsing | a common example of network use |
| Mobile phones | calls, messages, and apps |
| Schools | online classes and learning systems |
| Banks | online transactions and ATMs |
| Social media platforms | they work through computer networks |
| Smart homes | to control devices |
Why this topic matters
Every later topic in this chapter builds on this one. Topic 1.2 explains how a network is designed and how data travels inside it. Later topics cover network types, devices, topologies and protocols. All of them start from the same simple idea: devices that connect and communicate.
Practice this topic
Short questions
1.What is a computer network?2 marks
Answer
From the book: "A computer network allows different devices to connect and communicate with each other. It helps in sharing information quickly and easily." "Networks can connect computers, mobile phones, printers, and other digital devices" and "These devices communicate using cables or wireless signals." The book's Summary (p.17) gives the one-line definition: "A computer network is a group of connected computers and devices that share data, resources, and services."
2.Write two uses of computer networks.2 marks
Answer
Any two from the book's "Uses of Computer Network": "Internet browsing is a common example of network use. Mobile phones use networks for calls, messages, and apps. Schools use networks for online classes and learning systems. Banks use networks for online transactions and ATMs. Social media platforms work through computer networks. Smart homes also use networks to control devices."
3.Where are computer networks used?2 marks
Answer
From the book: "Computer networks are used in homes, schools, offices, and businesses. Modern life depends heavily on computer networks for daily tasks."
4.Which devices can a network connect, and how do they communicate?2 marks
Answer
From the book: "Networks can connect computers, mobile phones, printers, and other digital devices (as shown in Figure 1.1). These devices communicate using cables or wireless signals."
5.What does a network allow to move between devices? Can a network be of any size?2 marks
Answer
From the book: "A network allows data, files, and resources to move from one device to another. Networks can be small or large depending on the need."
6.Why are computer networks important in modern life?3 marks
Answer
From the book: a network "helps in sharing information quickly and easily. Communication through networks saves time and effort." "Modern life depends heavily on computer networks for daily tasks." The TIDBIT adds: "Networks support online learning and remote work. Businesses rely on networks for daily operations."
Long questions
1.Define a computer network. Explain its importance and uses in daily life.8 marks
Answer
Cover three parts, using the book's text from 1.1:
- Definition (verbatim): "A computer network allows different devices to connect and communicate with each other." Add: "Networks can connect computers, mobile phones, printers, and other digital devices (as shown in Figure 1.1). These devices communicate using cables or wireless signals." (Figure 1.1: A computer network connects multiple devices to share data and resources) The Summary (p.17) defines it in one line: "A computer network is a group of connected computers and devices that share data, resources, and services."
- Importance: "It helps in sharing information quickly and easily. Communication through networks saves time and effort. Computer networks are used in homes, schools, offices, and businesses. Modern life depends heavily on computer networks for daily tasks." "A network allows data, files, and resources to move from one device to another." TIDBIT: "Networks support online learning and remote work. Businesses rely on networks for daily operations."
- Uses in daily life (Uses of Computer Network): Internet browsing ("a common example of network use"); mobile phones "for calls, messages, and apps"; schools "for online classes and learning systems"; banks "for online transactions and ATMs"; "Social media platforms work through computer networks"; "Smart homes also use networks to control devices."
Aim for 200-300 words.
2.Explain what a computer network connects, how its devices communicate and what moves across it. Refer to Figure 1.1.5 marks
Answer
Use the 1.1 text and Figure 1.1:
- What it connects: "Networks can connect computers, mobile phones, printers, and other digital devices (as shown in Figure 1.1)." Figure 1.1 caption: "A computer network connects multiple devices to share data and resources".
- How devices communicate: "These devices communicate using cables or wireless signals."
- What moves: "A network allows data, files, and resources to move from one device to another."
- Size: "Networks can be small or large depending on the need."
- Why it helps: "It helps in sharing information quickly and easily. Communication through networks saves time and effort."
Aim for 150-200 words.
In this chapter
- 1.1Introduction to Computer NetworksYou are here
- 1.2Network Architecture and Basic Concepts
- 1.3Types of Computer Networks
- 1.4Networking Devices
- 1.5Network Topologies
- 1.6Network Models and Layers
- 1.7Network Protocols and Services
- 1.8IP Addressing and Subnetting
- 1.9Home Network Setup and Configuration
- 1.10Wi-Fi Security and Router Configuration
- 1.11Network Diagnostic Tools and Commands
- 1.12Network Performance
- 1.13Network Load Balancing
- 1.14Network Security
- 1.15Data Backup and Recovery
- 1.16Usability and Security Tradeoffs