Cambridge IGCSE Computer Science (0478) · lesson 14 of 35 · 20 min
Internet vs World Wide Web
These terms are often confused but are distinct:
HTTP and HTTPS
HTTP (HyperText Transfer Protocol) is the protocol used to request and send web pages between browsers and servers. It is a request-response protocol:
- Browser sends an HTTP GET request to the server.
- Server responds with the HTML file and a status code (200 OK, 404 Not Found, etc.).
- Browser renders the HTML, then requests any linked CSS, JS, and images.
HTTPS adds TLS/SSL encryption to HTTP. All data is encrypted in transit, preventing eavesdropping and tampering. Indicated by a padlock icon in the browser. Essential for login pages, banking, and any sensitive data.
HTML Basics
HTML (HyperText Markup Language) defines the structure and content of web pages using tags. Key tags:
<html>— root element<head>— metadata (title, CSS links)<body>— visible content<h1>–<h6>— headings<p>— paragraph<a href="url">— hyperlink<img src="file">— image
What is the difference between the Internet and the World Wide Web?
- They are the same thing
- The Internet is the infrastructure; the Web is a service on it
- The Web is the infrastructure; the Internet is a service
- The Internet only carries email
Answer: The Internet is the infrastructure; the Web is a service on it
The Internet is the physical/logical network; the Web is one service running on it.
What does HTTPS add to HTTP?
- Faster speeds
- TLS/SSL encryption
- Compression
- DNS resolution
Answer: TLS/SSL encryption
HTTPS = HTTP + TLS encryption for secure data transmission.
Which HTTP status code means “page not found”?
- 200
- 301
- 403
- 404
Answer: 404
404 = Not Found.
Previous lesson: The Internet: IP addresses, DNS, and packets
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