How the Web Works - Guided Notes

🌐 Networks and the Internet

What is a Network?

A network is _________________ or more computers connected together to share _________________

What is the Internet?

The Internet is a _________________ of _________________

It's the _________________ that carries data (like a highway system)

💡 Remember: The Internet is NOT the same as the World Wide Web!

Key Infrastructure Players

Component	What It Does	Example
ISP	_________________________________	Cox, AT&T
Router	_________________________________	Home router
Modem	_________________________________	Cable modem

📦 How Data Travels: Packets

What are Packets?

Packets are _________________________________________

Each Packet Contains:

_________________ address (where from)
_________________ address (where to)
Piece of the _________________
_________________ number (for reassembly)

Practice: Why do we use packets instead of sending data all at once?
_________________________________________
_________________________________________

🔢 IP Addresses and DNS

IP Addresses

An IP address is like a _________________ number for computers on the internet

Version	Format	Example
IPv4	_____ numbers (0-255)	192.168.1.1
IPv6	Much longer, _________________ format	2001:0db8:85a3:0000

DNS (Domain Name System)

DNS is the internet's _________________ book

It translates _________________ names (like google.com) into _________________ addresses

DNS Process:
1. You type: _________________
2. DNS Server looks up the _________________
3. Returns: _________________
4. Your browser connects to that _________________

💻 Client-Server Model

Client	Server
• _________________ information • Your web _________________ • Like a customer at a restaurant	• _________________ information • Hosts _________________ • Like the waiter/kitchen at a restaurant

Example Interaction:

Client says: "_________________________________________"

Server responds: "_________________________________________"

🔍 Web Components - Don't Mix These Up!

Define Each:

Web Browser:
_________________________________________
Examples: _________, _________, _________
Search Engine:
_________________________________________
Examples: _________, _________, _________
Web Page:
_________________________________________
Web Server:
_________________________________________

🔎 Journey of a Google Search

Fill in the Steps:

You type "google.com" → Browser checks its _________________
If not found, browser asks _________________ for IP address
DNS returns: _________________
Browser establishes _________________ with Google's server
Google sends back _________________, CSS, and JavaScript
You type search query and hit Enter
Query is _________________ (HTTPS) and sent to Google
Google searches its _________________ pages
Results returned in about _________________ seconds!

🌍 Internet vs. World Wide Web

Internet	World Wide Web
• The _________________ • Physical _________________ • Existed since _________________ • Includes email, FTP, gaming, etc.	• One _________________ on the internet • Web pages with _________________ • Created _________________ by Tim Berners-Lee • Uses _________________ protocol

💡 Analogy: The Web runs ON the Internet, like _________________________________________

🔒 Security: HTTP vs HTTPS

Compare:

HTTP	HTTPS
_________________ (not secure)	_________________ (secure)
Like sending _________________	Like sending _________________
Anyone can _________________	Only recipient can _________________

When should you look for HTTPS?
_________________________________________

✅ Quick Review Questions

What's the difference between a client and a server?
_________________________________________
_________________________________________
Why do we need DNS?
_________________________________________
_________________________________________
What are packets and why do we use them?
_________________________________________
_________________________________________
Browser vs. Search Engine - explain the difference:
_________________________________________
_________________________________________

🛠️ Practice Activity

Check Your Browser:

Visit: whatismybrowser.com

My browser: _________________

Version: _________________

Find Your IP:

Visit: whatismyipaddress.com

My IP address: _________________

My ISP: _________________

📝 Additional Notes

Use this space for any additional notes, questions, or insights from the lecture:

📚 Key Vocabulary to Remember

Term	Definition
Protocol	_________________________________________
TCP/IP	_________________________________________
Port	_________________________________________
Bandwidth	_________________________________________
Latency	_________________________________________