📚 Knowledge Library — Topic 5.2 — Internet

Requesting Web Pages Explained Simply

Follow the journey from typing a URL into a browser to seeing a web page on screen, with DNS, IP addresses, web servers, HTML and HTTPS kept clear and simple.

Start LearningWorked Example
1. Invitation

A web page does not just magically appear.

When you type a URL into a web browser, several steps happen very quickly in the background.

The browser has to find the correct web server, request the page, receive the page data, and display it on your screen.

💡 Remember: the browser does the requesting. The DNS only helps find the IP address.
Figure 1.1
From URL to Page
Type URL
↓
Find server
↓
Request page
↓
Display page
2. Big Idea

The browser needs a number before it can ask for the page.

Humans like readable names such as futurelogiceducation.com.

Computers use an IP address to locate the web server. A DNS looks up the domain name and returns the matching IP address to the browser.

💡 Key idea: URL first, DNS lookup second, IP address third, web server request fourth.
Figure 2.1
Name to Number
Domain name
↓
DNS lookup
↓
IP address
↓
Web server
3. FutureLogic Bridge

Think of ordering a parcel.

You know the company name, but the delivery driver needs the actual address.

The DNS is like a directory that turns the company name into the delivery address. Once the browser has the address, it can request the package from the web server.

💡 Bridge: URL = company name. DNS = directory. IP address = delivery address. Web page = parcel.
Figure 3.1
Parcel Delivery Model
Company name
↓
Directory finds address
↓
Parcel requested
↓
Parcel delivered
4. Worked Example

Follow the request step by step.

Cambridge often asks students to draw or describe this process.

Simple sequence

Browser sends URL to DNS
DNS returns IP address
Browser requests page
Model answer: "The browser sends the URL to a DNS, which finds the matching IP address and returns it to the browser. The browser then sends a request to the web server, which sends the HTML page data back to the browser."
Figure 4.1
Core Exam Sequence
Browser
→
DNS
→
Browser
→
Web server
5. Full Process

The complete journey has six clear steps.

Keep the steps in order. That is what makes the answer easy to follow.

StepWhat happens?
1User types the URL into the browser.
2Browser sends the URL to the DNS.
3DNS searches for the matching IP address.
4DNS returns the IP address to the browser.
5Browser sends a request to the web server.
6Web server sends HTML data back; browser renders the page.
Figure 5.1
Six-Step Route
URL
↓
DNS
↓
IP address
↓
Request
↓
HTML
↓
Rendered page
6. If DNS Cannot Find It

The request can be passed to another DNS.

Sometimes the first DNS does not have the matching IP address in its database.

If it cannot find the match, it can send the URL to another DNS in the hierarchy until the matching IP address is found.

💡 This extra step is often useful in diagram questions: if not found, the URL is sent to another DNS.
Figure 6.1
DNS Hierarchy
DNS 1 searches
↓
Not found?
↓
Send to DNS 2
↓
IP found
7. HTML and Rendering

The web server sends page data, not a screenshot.

The web server sends the web page data back to the browser. This often includes HTML, which is the language used to write web pages.

The browser then renders the HTML. Rendering means converting the code into the visual page the user sees.

💡 Browser job: receive HTML and render it into a readable web page.
Figure 7.1
Render HTML
<html>
<body>
Page data
</body>
</html>
↓
Visual page
8. HTTPS and SSL

Secure websites check identity before sending sensitive data.

HTTPS is the secure version of HTTP. It uses SSL/TLS to help create a secure connection between the browser and web server.

The web server sends a digital certificate to the browser. The browser validates it. If it is valid, the connection can be secure.

💡 Key detail: the server sends the certificate to the browser, not the other way round.
Figure 8.1
Secure Connection
Browser asks
↓
Server sends certificate
↓
Browser validates
↓
Secure connection
9. Exam Tip

Do not make the DNS do the browser's job.

A common mistake is to say the DNS sends the request to the web server.

That is not correct. The DNS returns the IP address to the browser. The browser then sends the request to the web server.

🎯 Exam Tip: DNS returns the IP address. Browser requests the web page.
Figure 9.1
Correct Roles
DNS
→
Returns IP address

Browser
→
Requests web page
10. Common Mistake

Fix the direction of the request.

Students often understand the parts, but put them in the wrong order.

⚠️ Common Mistake:

Student answer: "The DNS sends a request to the web server for the web page."

❌ This loses marks because the DNS does not request the web page. It only finds and returns the matching IP address.

Better answer: "The DNS returns the matching IP address to the browser. The browser then sends a request to the web server for the web page data."
Figure 10.1
Better Exam Wording
Wrong
DNS → server

↓

Correct
DNS → browser
Browser → server
11. Summary

Requesting a web page in one screen.

The browser sends the URL to a DNS. The DNS searches for the matching IP address and returns it to the browser.

The browser uses the IP address to request the web page from the web server. The web server sends HTML data back, and the browser renders it into a visible page.

For secure sites, HTTPS uses SSL/TLS and digital certificates to help establish a secure connection.

💡 Key idea: DNS finds the address. Browser requests the page. Web server sends the page data.
Figure 11.1
5.2 Summary
URL typed
↓
DNS returns IP
↓
Browser requests page
↓
Server sends HTML
↓
Browser renders page