INTERNET, HTTP, AND HTTPS IN SIMPLE WORDS

This note explains the basics of the Internet, HTTP, and HTTPS in simple language.

You will learn:

1. what a protocol is
2. what HTTP is
3. how the browser talks to the server
4. what happens during a request
5. what DNS does
6. what HTTPS is
7. why HTTPS is safer than HTTP

1. What is a protocol?

A protocol is a set of rules.

These rules help devices understand how to send and receive data.

Without protocols, computers would not know:

• how to start communication
• how to send data
• how to receive data
• how to understand the response

Easy definition:

Protocol = rules for communication between devices

Diagram 1. Protocol idea

Computer A
-> follows rules
-> sends data
-> follows rules
-> Computer B

Both sides must follow the same rules. That is why protocols are important.

2. What is HTTP?

HTTP means:

HyperText Transfer Protocol

It is a common protocol for transferring web resources such as:

• HTML
• CSS
• JavaScript
• images
• audio
• video

When you open a website, your browser sends a request to a server.

Then the server sends back the needed files. This usually happens through HTTP.

Diagram 2. HTTP basic idea

Browser
-> request
Server
-> response
Browser gets website files

HTTP is the rule system that helps the browser and server exchange web data.

3. Client and server

HTTP works using the client-server model.

Client

The client is usually the browser.

Examples:

• Chrome
• Firefox
• Edge
• Safari

Server

The server is the computer that stores the website files and sends them back.

Browser = client
Website computer = server

Diagram 3. Client-server model

Client (browser)
-> asks for data
Server
-> sends data back
Client shows page

The browser asks. The server answers. This is the main idea of web communication.

4. Request-response model

HTTP uses the request-response model.

That means:

1. the client sends a request
2. the server processes it
3. the server sends a response
4. the client receives and shows the result

Diagram 4. Request-response model

Step 1: Browser sends request
Step 2: Server receives request
Step 3: Server prepares response
Step 4: Browser receives response

This happens again and again while you use websites.

For one page, the browser may send many requests:

• one for HTML
• one for CSS
• one for JavaScript
• many for images

5. What happens when you open a website?

Suppose you type a website address in the browser.

Example:

google.com

The browser must do several things before the page appears.

Diagram 5. Full path from browser to website

Enter website address
-> find server IP address
-> connect to server
-> send request
-> wait for response
-> receive data
-> show website

The browser does not instantly know where the website is. It must first find the correct server.

6. DNS request

A website address like google.com is easy for humans.

But computers work with IP addresses, for example:

74.125.87.99

So the browser must first find the IP address of the website.

This is done through DNS.

DNS means:

Domain Name System

DNS converts a domain name into an IP address.

Diagram 6. DNS conversion

google.com
-> DNS
-> 74.125.87.99

DNS works like a phone book. You know the website name. DNS finds the numeric address.

7. Main stages of a request

A request usually goes through these stages:

1. DNS request
2. connection
3. data transfer
4. waiting for response
5. receiving data

7.1 DNS request

The browser finds the IP address of the website.

google.com -> 74.125.87.99

7.2 Connection

After the browser gets the IP address, it creates a connection to the server.

Now the client and server can start communicating.

7.3 Data transfer

The browser sends request data to the server.

For example:

• which page is needed
• what resource is needed

7.4 Waiting for response

Now the browser waits.

The request must:

• reach the server
• be processed
• get a response back

7.5 Receiving data

When the response arrives, the browser receives the data and starts using it.

For example:

• render HTML
• load CSS
• run JavaScript
• show images

Diagram 7. Request stages

1. DNS request
-> 2. Connection
-> 3. Data transfer
-> 4. Waiting for response
-> 5. Receiving data

This full process is repeated many times while a website loads.

8. What is HTTPS?

HTTPS means:

HyperText Transfer Protocol Secure

It is a secure version of HTTP.

The main difference is:

HTTPS encrypts the data
HTTP does not

Diagram 8. HTTP vs HTTPS

HTTP
-> data sent as plain text

HTTPS
-> data sent in encrypted form

This is the most important difference between them.

9. Why HTTP is less secure

With regular HTTP, data is sent as plain text.

That means if someone gets access to the connection, they may be able to read the data.

This is dangerous for information like:

• passwords
• addresses
• payment details
• credit card numbers

Diagram 9. HTTP problem

Browser
-> plain text data
Network
-> Server

If attacker can see connection
-> data may be readable

That is why HTTP is not safe for sensitive information.

10. Why HTTPS is safer

With HTTPS, the data between the browser and the server is encrypted.

That means even if someone intercepts the data, they cannot read it in normal form.

HTTPS uses security technologies like:

• SSL
• TLS

These cryptographic protocols protect the connection.

Diagram 10. HTTPS protection

Browser
-> encrypted data
Network
-> encrypted data
Server

Attacker sees encrypted data
-> cannot read it normally

This is why HTTPS is much safer than HTTP.

11. Why encryption matters

Imagine a user buys something in an online store and enters:

• card number
• address
• personal details

If this is sent with plain HTTP, it is much easier to steal.

If this is sent with HTTPS, the data is encrypted. That makes stealing readable information much harder.

Diagram 11. Shopping example

User enters payment data
-> HTTP
-> plain text risk

User enters payment data
-> HTTPS
-> encrypted safer transfer

This is why secure websites use HTTPS.

12. How to recognize HTTPS

In the browser address bar, secure websites usually show:

• a lock icon
• https:// at the beginning of the address

Example:

https://example.com

Diagram 12. Secure website signs

Address bar
-> lock icon
-> https://

This usually tells the visitor that the connection is protected.

13. Main difference between HTTP and HTTPS

The correct main difference is:

HTTPS is more secure than HTTP because it encrypts the data sent between the browser and the server.

That is the most important thing to remember.

Diagram 13. Final comparison

HTTP
-> faster to explain
-> but not secure enough for sensitive data

HTTPS
-> secure
-> encrypted
-> better for real websites

In modern web development, HTTPS is the standard for safe communication.

14. Easy memory rules

Protocol = communication rules
HTTP = browser and server exchange web resources
Client = browser
Server = website computer
Request = browser asks
Response = server answers
DNS = name to IP address
HTTPS = secure HTTP with encryption

15. Quick summary

• A protocol is a set of rules for communication.
• HTTP is a protocol for transferring web resources.
• HTTP works with the client-server model.
• The browser sends a request, and the server sends a response.
• Before connecting, the browser often uses DNS to convert a domain into an IP address.
• A request usually goes through DNS, connection, data transfer, waiting, and receiving data.
• HTTPS is a secure version of HTTP.
• HTTPS encrypts transmitted data.
• HTTP sends data in plain text, so it is less secure.
• Secure websites usually show a lock icon and use https://.

16. Final conclusion

If you understand these ideas:

protocol
HTTP
HTTPS
client
server
request
response
DNS
encryption

then you already have a strong foundation for understanding how websites communicate on the Internet.

This topic is very important because every website depends on these rules to load and work correctly.