What is a computer network?
A computer network is a group of connected devices that can communicate and exchange information. Devices may include computers, phones, servers, printers, routers and other network equipment.
Networks can be very small, such as a few devices connected in a home, or extremely large, such as the systems that make up the internet.
Why do networks matter?
Networks allow people and systems to share information and services. Students use networks when accessing websites, sending messages, joining online classes, downloading files or using cloud applications.
A Simple Example
Your computer → Wi-Fi router → internet service → remote server → website or application.
Common network devices
Different devices perform different jobs inside a network.
- Router: connects networks and helps direct traffic between them.
- Switch: connects devices within a local network.
- Access Point: provides wireless network connectivity.
- Server: provides resources or services to other systems.
- Client Device: uses network resources or services.
What is an IP address?
An IP address identifies a device or network interface so that network traffic can be directed to the appropriate destination.
Two major versions are commonly discussed: IPv4 and IPv6.
Example IPv4 Address
192.168.1.10
Private IPv4 addresses such as this are commonly used inside local networks.
What are network protocols?
A protocol is a set of rules that allows systems to communicate in a predictable way.
Different protocols are used for different purposes. Web communication, email, file transfer and name resolution all rely on defined networking protocols.
What is the internet?
The internet is a global network of interconnected networks. It allows systems in different locations to communicate using standardized technologies and protocols.
When you open a website, information may travel through several networks and devices before reaching the server hosting that website.
Local networks and wide networks
A local area network, or LAN, usually connects devices across a limited physical area such as a home, office, laboratory or school.
A wide area network, or WAN, connects networks across larger geographic areas.
Think About the Difference
LAN → smaller physical area.
WAN → larger geographic area connecting networks.
How data travels
Data sent across a network is handled according to networking rules and technologies. Information may be divided into smaller units and sent across multiple network devices before reaching its destination.
The receiving system processes the information and reconstructs the communication according to the protocols being used.
Network security basics
Networks should be protected against unauthorized access and misuse. Basic security practices can include strong authentication, secure wireless configuration, firewalls, software updates and appropriate access controls.
Students learning networking should also understand that connected systems create security responsibilities.
Key terms to remember
- Network
- Router
- Switch
- Server
- Client
- IP address
- Protocol
- LAN
- WAN
- Internet
Quick review
Question 1
What is the main purpose of a computer network?
Question 2
What is an IP address used for?
Question 3
What is one difference between a LAN and a WAN?
Final thoughts
Computer networks provide the communication foundation behind many digital services. Understanding devices, addresses, protocols and basic network types gives students a useful foundation for later topics in networking, cloud computing and cybersecurity.