Unit IV: Introduction to Internet and WWW

Course: Fundamentals of Information Technology
Code: CADSC101

Table of Contents

Basics of Computer Networks
LAN, MAN, and WAN
Network Topology
Concept of Internet & WWW
IP Address, URL, and ISP
Modes of Connecting Internet
Surfing the Web & Search Engines
Exam Focus: Tips & FAQs

Basics of Computer Networks

A computer network is a collection of computers and other hardware components interconnected by communication channels that allow sharing of resources and information.

LAN, MAN, and WAN

Networks are categorized based on the geographical area they cover.

Type	Full Form	Description
LAN	Local Area Network	Covers a small area like a room, home, or office building.
MAN	Metropolitan Area Network	Connects multiple LANs across a city or a large campus.
WAN	Wide Area Network	Covers a broad area such as a country, continent, or the whole world.

Network Topology

Network topology refers to the physical or logical arrangement of computers or nodes in a network. Common types include:

Bus Topology: All nodes are connected to a single central cable.
Star Topology: All nodes are connected to a central hub or switch.
Ring Topology: Each node is connected to exactly two other nodes, forming a circle.
Mesh Topology: Every node is connected to every other node.

Concept of Internet & WWW

Internet: A global system of interconnected computer networks that use the Internet protocol suite (TCP/IP) to link devices worldwide.
WWW (World Wide Web): A system of interlinked hypertext documents accessed via the Internet.

IP Address, URL, and ISP

IP Address: A unique numerical label assigned to each device connected to a computer network.
Website Address and URL: Uniform Resource Locator (URL) is the global address of documents and other resources on the World Wide Web.
ISP (Internet Service Provider): An organization that provides services for accessing, using, or participating in the Internet.

Modes of Connecting Internet

There are several ways to connect a device to the Internet:

Hotspot: Using a mobile device's cellular data to create a local Wi-Fi network.
Wi-Fi: Wireless networking technology that allows devices to interface with the Internet.
LAN Cable: Physical ethernet connection for high-speed stability.
Broadband: High-speed Internet access that is always on.
USB Tethering: Connecting a phone to a computer via USB to share the phone's internet connection.

Surfing the Web & Search Engines

Exploring the Internet involves "surfing" through web pages using specialized tools.

Search Engines: Tools used to search for information on the World Wide Web (e.g., Google, Bing).
Downloading/Printing: Saving web pages for offline use or creating physical copies.

Exam Focus & Tips

Exam Tip: Be ready to differentiate between the Internet and the World Wide Web; they are not the same thing.
Common Mistake: Confusing URL with IP Address. A URL is the human-readable name (www.google.com), while an IP is the machine-readable number.
Mnemonic: LMW - Local (Small), Metropolitan (City), Wide (World).

Frequently Asked Questions

Q: What is the role of an ISP?
A: To provide the infrastructure and services needed for users to connect to the Internet.

Q: Name three network topologies.
A: Bus, Star, and Ring.