Internet Basics: How the Internet Works, Key Terms and Services

The internet is an important part of computer networking. It connects computers, smartphones, servers and smaller networks around the world.

The internet allows users to:

Open websites
Send emails
Make video calls
Watch online videos
Share files
Use social media
Play online games
Access cloud services
Shop and bank online

In simple words, the internet is a worldwide network of connected networks.

What Is the Internet?

The internet is a global system that connects millions of private, public, business, educational and government networks.

These networks communicate using standard rules called protocols.

The term “internet” comes from interconnected networks.

Real-Life Example

Your home has a small network containing:

Smartphones
Laptops
Smart televisions
A Wi-Fi router

A school, bank and company also have their own networks.

The internet connects these separate networks so their devices can exchange authorised information across different locations.

Internet Explained With a Real-Life Example

The internet works like a global road and delivery system.

Delivery System	Internet
House	Computer or network
Street address	IP address
Parcel	Data
Roads	Cables and wireless links
Road junction	Router
Delivery company	Internet Service Provider
Delivery rules	Internet protocols
Sorting office	Data centre or network facility

When a parcel is sent, it passes through different roads and sorting points before reaching its destination.

Similarly, internet data passes through different networks and routers before reaching the correct server or device.

Is the Internet a Computer Network?

Yes. The internet is part of computer networking.

However, it is not one single local network. It is a global collection of interconnected networks.

These networks include:

Home networks
School networks
Office networks
Mobile networks
Data-centre networks
Government networks
Internet-provider networks

Real-Life Example

Your home LAN connects to your internet provider. The provider connects to other networks, which connect to servers and networks around the world.

Who Owns the Internet?

No single person or company owns the entire internet.

Different organisations own and manage different parts, including:

Fibre-optic cables
Mobile networks
Data centres
Servers
Routers
Undersea cables
Domain-name systems
Websites and online services

Standards organisations, service providers, governments and network operators help the internet function together.

Real-Life Example

No single company owns every road in the world. Different authorities and organisations manage different roads, but the roads connect to form a large transport system.

The internet works in a similar way.

What Is Required to Use the Internet?

A user normally needs:

An internet-capable device
A network interface
A router or access point when required
A modem, fibre ONT or other connection equipment
An Internet Service Provider
A wired, wireless or mobile connection
Networking software and protocols

Internet-Capable Device

The user needs a device such as:

Computer
Laptop
Smartphone
Tablet
Smart television
Gaming console

Real-life example: A smartphone uses Wi-Fi or mobile data to access the internet.

Network Interface

A network interface allows the device to connect through Ethernet, Wi-Fi, mobile technology or another supported method.

Real-life example: The Wi-Fi adapter inside a laptop connects it to a wireless router.

Router

A router connects your local network to other networks.

It directs data towards its destination.

Real-life example: A router acts like a road junction that sends vehicles in the correct direction.

Modem or ONT

A modem connects a network to certain types of internet service, such as cable or DSL.

Fibre connections commonly use an Optical Network Terminal, or ONT, to connect the provider’s fibre service.

A single device supplied by an internet provider may combine modem, router, switch and wireless access-point functions.

Real-life example: This equipment acts as the entrance between your home network and your internet provider.

Internet Service Provider

An Internet Service Provider, or ISP, is a company that provides internet connectivity.

The ISP connects your home, phone or business to its network and then to other networks.

Real-life example: An ISP is similar to a transport company that provides access to a larger road system.

How Does the Internet Work?

The internet sends data in small units called packets.

When you request information:

Your device creates a request.
The request is divided into packets.
Packets receive source and destination information.
Your router forwards the packets to your ISP.
Routers move the packets through different networks.
The destination server receives the request.
The server sends the requested data back.
Your device receives and reassembles the packets.
The application displays the information.

What Happens When You Open a Website?

Suppose you enter a website address into your browser.

Step 1: You Enter the URL

You type the website’s URL into the browser.

The URL tells the browser which resource you want to access.

Step 2: DNS Finds the IP Address

Computers communicate using IP addresses, but people usually remember domain names more easily.

The Domain Name System finds the IP address connected to the domain name.

Real-life example: DNS works like a contact list that finds a phone number from a person’s name.

Step 3: The Browser Creates a Request

The browser prepares an HTTP or HTTPS request for the website.

If HTTPS is used, the browser and server establish protected communication using TLS.

Step 4: The Request Reaches the Router

Your device sends the request through Wi-Fi or Ethernet to the local router.

Step 5: The ISP Receives the Request

The router forwards the request to your Internet Service Provider.

Step 6: Routers Select a Path

The packets travel through multiple routers and networks towards the website server.

Different packets may sometimes follow different available paths.

Step 7: The Server Processes the Request

The server identifies the requested page and prepares a response.

Step 8: Data Returns to Your Device

The server sends the website’s data back as packets.

The response may include:

HTML
CSS
JavaScript
Images
Fonts
Video or other resources

Step 9: The Browser Displays the Page

The browser processes the received files and displays the website on your screen.

This complete process can happen within a fraction of a second or a few seconds, depending on the connection and server.

What Is a Data Packet?

A packet is a small unit of data sent across a network.

A packet can contain:

Part of the original data
Source address
Destination address
Protocol information
Control information

The receiving device combines the packets to recreate the original content.

Real-Life Example

Imagine sending a large cupboard to another city. It is separated into smaller numbered parts, transported and rebuilt at the destination.

Internet data is transferred in a similar way.

What Is an IP Address?

An IP address identifies a device or network interface for communication using the Internet Protocol.

Two main versions are used:

IPv4
IPv6

Real-Life Example

An IP address is like a postal address. It helps the network deliver data towards the correct destination.

IPv4

IPv4 uses 32-bit addresses.

An example format is:

192.168.1.10

The available IPv4 address space is limited, so technologies such as private addressing and NAT are widely used.

IPv6

IPv6 uses 128-bit addresses.

It provides a much larger address space than IPv4.

An IPv6 address can contain numbers and letters separated by colons.

Public IP Address

A public IP address is used to communicate across the internet.

It is normally assigned through an Internet Service Provider or hosting provider.

Real-life example: A public IP address is similar to the public street address of a house.

Private IP Address

A private IP address is used inside a local network.

Devices in homes and offices commonly receive private addresses from their routers.

Real-life example: Private addresses are like the individual room numbers inside a house.

What Is NAT?

NAT stands for Network Address Translation.

NAT allows multiple devices using private IP addresses to share a public IP address when accessing the internet.

Real-Life Example

Family members live in different rooms but share one public house address. The router keeps track of which internet response belongs to which local device.

What Is a Domain Name?

A domain name is a human-readable name used to access an internet resource.

A domain name is easier to remember than a numerical IP address.

Real-Life Example

Saving a person’s name in your contact list is easier than remembering their phone number. A domain name serves a similar purpose.

What Is DNS?

DNS stands for Domain Name System.

DNS translates domain names into IP addresses.

DNS Process

The user enters a domain name.
The device asks a DNS resolver for its IP address.
The resolver checks available records or asks other DNS servers.
The correct address is returned.
The browser connects towards the website server.

Real-Life Example

DNS works like asking a directory service for the address of a business.

What Is a URL?

URL stands for Uniform Resource Locator.

A URL is the complete address of a resource on the internet.

A URL may contain:

Protocol
Domain name
Path
Query information
Fragment

Example structure:

https://example.com/computer-networks

In this example:

https is the protocol
example.com is the domain
/computer-networks is the path

Website, Web Page and Homepage

Term	Meaning	Real-Life Example
Website	Collection of related web pages	A complete educational site
Web Page	One individual page	One lesson on computer networks
Homepage	Main starting page of a website	The website’s front page

A website is like a book, while web pages are like individual pages or chapters inside it.

What Is a Web Browser?

A web browser is an application used to access and display websites.

A browser can:

Request web pages
Display text and images
Play supported media
Run web applications
Store browsing data
Manage downloads

Real-Life Example

A browser is like a vehicle used to travel through the World Wide Web.

What Is a Search Engine?

A search engine helps users find web pages and online information.

It collects and organises information from websites and shows relevant results for a search query.

Real-Life Example

A search engine is like a library catalogue that helps you find a book, while a browser is the tool used to open and read it.

Browser vs Search Engine

Browser	Search Engine
Software installed or available on a device	Online service accessed through a browser or app
Opens and displays websites	Finds information and web pages
Can directly open a URL	Searches using keywords
Example function: display a page	Example function: list relevant pages

A browser and search engine perform different jobs.

Internet vs World Wide Web

The internet and the World Wide Web are related, but they are not the same.

Internet	World Wide Web
Global network infrastructure	System of connected websites and web pages
Connects devices and networks	Uses the internet to deliver web content
Supports many services	One service that operates through the internet
Includes email, file transfer and calls	Mainly accessed using browsers

Real-Life Example

The internet is like the road network, while the Web is one type of service travelling on those roads.

Email uses the internet, but email is not the World Wide Web.

Types of Internet Connections

Fibre Internet

Fibre connections use light signals travelling through fibre-optic cables.

They can provide:

High speed
High capacity
Low latency
Reliable long-distance communication

Real-life example: A home connected through full fibre uses an optical cable to reach the provider’s network.

Cable Internet

Cable internet uses coaxial cable infrastructure.

It can provide high speeds, but performance may be affected by local network demand.

Real-life example: Multiple homes in an area may share parts of the provider’s cable network.

DSL

DSL provides internet service through telephone-line infrastructure.

Its performance depends on the technology and distance from the provider’s equipment.

Real-life example: An older home internet connection may use the same line infrastructure as a landline telephone.

Mobile Internet

Mobile internet uses cellular networks such as 4G or 5G.

It is used by:

Smartphones
Tablets
Mobile hotspots
Compatible routers

Real-life example: Your phone uses mobile data when Wi-Fi is unavailable.

Fixed Wireless Internet

Fixed wireless uses radio signals between a fixed receiver and the provider’s equipment.

Real-life example: A receiver installed on a building connects wirelessly to a nearby provider tower.

Satellite Internet

Satellite internet sends data through satellites and ground equipment.

It can provide connectivity in remote locations where cable-based services are unavailable.

Real-life example: A house in an isolated rural area may use a satellite dish for internet access.

Public Wi-Fi

Public Wi-Fi is provided in places such as:

Cafés
Airports
Hotels
Libraries
Shopping centres

Public Wi-Fi should be used carefully because other users share the network.

Wi-Fi vs Internet

Wi-Fi and the internet are not the same.

Wi-Fi connects a device wirelessly to a local network.
The internet connects networks around the world.

Real-Life Example

Your phone can remain connected to your home Wi-Fi router even when the provider’s internet service is down.

In this situation:

Wi-Fi is working.
The local network is working.
Internet access is unavailable.

Can the Internet Work Without Wi-Fi?

Yes. Wi-Fi is only one method of connecting to a network.

The internet can also be accessed through:

Ethernet
Mobile data
Fibre
Cable
DSL
Fixed wireless
Satellite

Real-life example: A desktop computer connected through Ethernet can access the internet without using Wi-Fi.

Internet Speed, Bandwidth and Latency

Bandwidth

Bandwidth is the maximum amount of data a connection can carry during a period.

It is commonly measured in:

Mbps
Gbps

Real-life example: Bandwidth is like the width of a road. A wider road can carry more vehicles at the same time.

Download Speed

Download speed measures how quickly data is received.

Real-life example: Watching a video or downloading a game uses download capacity.

Upload Speed

Upload speed measures how quickly data is sent.

Real-life example: Uploading a video or sending a large backup uses upload capacity.

Latency

Latency is the delay between sending data and receiving a response.

It is normally measured in milliseconds.

Real-life example: High latency can cause a noticeable delay during an online game or video call.

Throughput

Throughput is the amount of useful data actually transferred.

It may be lower than the advertised connection speed because of:

Network congestion
Wi-Fi interference
Server limitations
Protocol overhead
Device performance
Distance and signal quality

Important Internet Protocols

Internet protocols are rules used by devices and applications to communicate.

TCP

TCP stands for Transmission Control Protocol.

TCP helps provide reliable and ordered delivery of data.

Real-life example: TCP is like checking that every numbered part of a parcel arrived in the correct order.

UDP

UDP stands for User Datagram Protocol.

UDP sends data with less delivery checking, which can reduce delay.

Real-life example: During a live call, receiving the next sound quickly can be more useful than stopping to recover a small missed part.

IP

IP stands for Internet Protocol.

IP provides addressing and helps packets travel between networks.

Real-life example: IP is similar to the addressing system used by a delivery company.

HTTP

HTTP stands for Hypertext Transfer Protocol.

HTTP is used to transfer web content between browsers and servers.

HTTPS

HTTPS stands for Hypertext Transfer Protocol Secure.

HTTPS protects web communication using encryption and server authentication provided through TLS.

A padlock or HTTPS connection means the connection is encrypted. It does not automatically guarantee that the website itself is honest or safe.

DHCP

DHCP stands for Dynamic Host Configuration Protocol.

DHCP automatically provides network settings to devices.

Real-life example: Your router normally gives your phone a private IP address when it joins Wi-Fi.

SMTP

SMTP stands for Simple Mail Transfer Protocol.

It is mainly used for sending email.

IMAP and POP3

IMAP and POP3 are used by email applications to access messages.

IMAP commonly keeps the mailbox synchronised across devices.

FTP and SFTP

FTP is used to transfer files.

SFTP transfers files through a secure SSH connection.

Common Internet Services

World Wide Web

The Web provides websites and web applications.

Real-life example: Reading an online article through a browser.

Email

Email allows users to send and receive digital messages.

Real-life example: Sending an assignment to a teacher.

Voice and Video Communication

The internet supports voice calls, video meetings and online classes.

Real-life example: Employees in different countries join the same video meeting.

File Transfer

Users can upload, download and share files.

Real-life example: Uploading a document to an online learning platform.

Streaming

Streaming delivers audio or video while it is being played.

Real-life example: Watching a movie without downloading the entire file first.

Cloud Services

Cloud services provide online storage, applications and computing resources.

Real-life example: Editing a document that is stored and synchronised online.

Social Networking

Social networking services allow users to communicate and share content.

Real-life example: Posting a photograph that friends can view online.

Online Gaming

Online games allow players in different locations to interact.

Real-life example: Players in two countries join the same game server.

E-Commerce

E-commerce allows users to buy and sell products online.

Real-life example: Ordering groceries through a website or application.

Online Banking

Online banking allows authorised users to access financial services remotely.

Real-life example: Checking an account balance through a secure banking application.

Intranet and Extranet

Intranet

An intranet is a private internal network or web-based system used by an organisation.

Real-life example: A company portal that only employees can access.

Extranet

An extranet gives selected external users controlled access to part of an organisation’s private system.

Real-life example: A supplier uses a company portal to check purchase orders.

Internet Security Basics

Use Strong Passwords

Use long, unique passwords for important accounts.

Avoid reusing the same password everywhere.

Enable Multi-Factor Authentication

Multi-factor authentication requires an additional verification method.

Real-life example: After entering a password, the user confirms a code or approval request.

Check HTTPS

Use HTTPS when entering sensitive information.

Remember that HTTPS protects the connection but does not prove every website is trustworthy.

Be Careful With Links

Do not open unexpected links or attachments without checking them.

Real-life example: A fake email may direct you to a copied login page designed to steal your password.

Keep Software Updated

Updates can repair known security weaknesses.

Update:

Operating systems
Browsers
Applications
Routers
Security software

Protect Personal Information

Do not share sensitive information unnecessarily.

This includes:

Passwords
Banking details
Identification documents
Private addresses
Verification codes

Use Public Wi-Fi Carefully

Avoid sensitive activity on unknown public networks unless suitable protection is used.

Confirm that the network name belongs to the real organisation.

Download From Trusted Sources

Unknown files may contain malware.

Use official or trusted sources when downloading applications and documents.

Create Backups

Keep important information in more than one secure location.

A backup can help after:

Device failure
Accidental deletion
Malware
Account loss

Advantages of the Internet

Fast global communication
Easy access to information
Online education
Remote working
Digital banking
Online shopping
Entertainment
File sharing
Cloud storage
Business opportunities
Access to government services
Collaboration across different locations

Real-Life Example

A student can attend an online class, download study material and communicate with a teacher from home.

Limitations and Risks of the Internet

Cyberattacks
Phishing
Malware
Misinformation
Privacy loss
Online fraud
Account theft
Harmful content
Internet addiction
Service outages
Unequal access
Dependence on online services

Real-Life Example

A fake shopping website may collect payment information without delivering a real product.

A Short History of the Internet

ARPANET

ARPANET was an early packet-switching network developed in the United States. Its first connections were made in 1969.

TCP/IP Adoption

On 1 January 1983, ARPANET adopted TCP/IP as its standard communication method. This date is often treated as an important milestone in the development of the modern internet.

World Wide Web

Tim Berners-Lee proposed the World Wide Web in 1989. The Web made it easier to access connected documents through browsers, web servers and links.

The internet existed before the Web. The Web became one of the most widely used internet services.

Frequently Asked Questions

What is the internet in simple words?

The internet is a worldwide system that connects computers, devices and smaller networks.

Is the internet part of computer networking?

Yes. Internet communication uses computer networks, networking devices, addresses and protocols.

Is Wi-Fi the same as the internet?

No. Wi-Fi connects devices to a local network. The internet connects networks around the world.

Can Wi-Fi work without the internet?

Yes. Local devices can remain connected through Wi-Fi even when internet access is unavailable.

Can the internet work without Wi-Fi?

Yes. Internet access can use Ethernet, mobile data, fibre, cable, DSL, satellite or another supported connection.

What is the difference between the internet and the Web?

The internet is the global network infrastructure. The Web is a service that uses the internet to provide websites and web pages.

What is an ISP?

An ISP is a company that provides internet connectivity.

What is an IP address?

An IP address identifies a device or network interface for communication using the Internet Protocol.

What is DNS?

DNS translates a domain name into an IP address.

What is a URL?

A URL is the complete address of an online resource.

What is a data packet?

A packet is a small unit of data transmitted through a network.

What does HTTPS mean?

HTTPS means Hypertext Transfer Protocol Secure. It protects communication between a browser and server using encryption and authentication.

Why can actual internet speed be lower than advertised speed?

Actual performance can be affected by Wi-Fi signal quality, network congestion, server speed, device performance and communication overhead.

Conclusion

The internet is a global collection of interconnected computer networks.

When a user opens a website:

DNS finds the server’s IP address.
The browser creates a request.
The data travels through the router and ISP.
Internet routers forward packets towards the server.
The server sends the requested information back.
The browser displays the content.

Important internet concepts include:

IP addresses
DNS
URLs
Web browsers
Search engines
Data packets
Internet protocols
Bandwidth and latency
Online security

In simple words, the internet connects networks around the world so devices can communicate and share information.