Exercise Solutions Available
Step-by-step answers for all textbook questions in this chapter
Introduction to Internet and Email: Exercise Solutions
How to Use This Page
Read the Samacheer Kalvi textbook chapter first. Then use this page to revise: attempt the textbook questions on your own, then compare with the model answers below. Pay special attention to the Common Mistakes section and the Exam Checklist before your test.
Key Concepts (Quick Recap)
| Term | Definition |
|---|---|
| Internet | A global network of interconnected computers communicating using standard protocols (TCP/IP) |
| World Wide Web (WWW) | A service on the internet that uses HTTP and browsers to access web pages |
| Browser | Software used to access and view websites (e.g. Chrome, Firefox, Edge) |
| Search Engine | A program that searches the internet for documents containing specified keywords (e.g. Google, Bing) |
| URL | Uniform Resource Locator — the address used to locate a resource on the internet |
| HTTP | HyperText Transfer Protocol — the protocol used to transfer web pages |
| HTTPS | HTTP Secure — HTTP with encryption for secure data transfer |
| HTML | HyperText Markup Language — the language used to create web pages |
| Electronic mail — a method of exchanging digital messages over the internet | |
| SMTP | Simple Mail Transfer Protocol — used for sending email |
| POP3 | Post Office Protocol version 3 — used for receiving email (downloads and deletes from server) |
| IMAP | Internet Message Access Protocol — used for receiving email (syncs with server) |
| ISP | Internet Service Provider — a company that provides internet access |
| IP Address | A unique numerical address assigned to each device on the internet (e.g. 192.168.1.1) |
| Domain Name | A human-readable name that maps to an IP address (e.g. google.com) |
| DNS | Domain Name System — translates domain names to IP addresses |
| Modem | A device that modulates and demodulates signals for internet communication |
| Bandwidth | The maximum rate of data transfer across a network connection |
I. Choose the Correct Answer (MCQ)
Q1. The internet is a _________.
(a) Single computer (b) Network of networks ✓ (c) Software (d) Operating system
Q2. Which protocol is used for sending email?
(a) POP3 (b) IMAP (c) SMTP ✓ (d) FTP
Q3. A URL stands for _________.
(a) Uniform Resource Locator ✓ (b) Universal Remote Locator (c) Unique Resource Language (d) Unified Resource Link
Q4. Which of the following is a web browser?
(a) Google Chrome ✓ (b) Google (c) Windows (d) MS Office
Q5. The full form of WWW is _________.
(a) Wide World Web (b) World Wide Web ✓ (c) World Web Wide (d) Web World Wide
Q6. DNS stands for _________.
(a) Domain Name System ✓ (b) Digital Name Service (c) Data Network System (d) Domain Network Service
Q7. POP3 is used for _________.
(a) Sending email (b) Receiving email ✓ (c) Browsing the web (d) File transfer
Q8. Which of the following is an example of a domain name?
(a) 192.168.1.1 (b) www.google.com ✓ (c) http:// (d) chrome.exe
Q9. An IP address is a _________.
(a) Text address (b) Numerical address ✓ (c) Email address (d) Website name
Q10. The protocol used for secure web browsing is _________.
(a) HTTP (b) FTP (c) HTTPS ✓ (d) SMTP
II. Very Short Answer Questions (2 Marks)
Q1. What is the internet?
Q2. What is a web browser?
Q3. What is a search engine?
Q4. Define URL.
- Protocol: http:// or https://
- Domain name: www.example.com
- Path: /page.html
- Example: https://www.example.com/about.html
Q5. What is an IP address?
Q6. What is an ISP?
III. Short Answer Questions (3 Marks)
Q1. Differentiate between the internet and the World Wide Web.
| Feature | Internet | World Wide Web |
|---|---|---|
| Definition | A global network of interconnected computers | A service that runs on the internet |
| Scope | Broader — includes all services | Narrower — one of many internet services |
| Protocols | TCP/IP, FTP, SMTP, etc. | HTTP, HTTPS |
| What it provides | Network connectivity and infrastructure | Web pages, websites, hyperlinked content |
| Relationship | The infrastructure | An application built on the internet |
| Other services | Email, FTP, Telnet, VoIP | Web browsing only |
The internet is the underlying network infrastructure, while the World Wide Web is one of the many services that run on top of it. The web uses browsers and HTTP to access web pages, whereas the internet supports many other services beyond web browsing.
Q2. Explain the different types of internet connections.
1. Dial-up Connection: Uses a telephone line and a modem to connect to the internet. It is slow (up to 56 Kbps) and ties up the phone line. The connection must be established each time you want to go online.
2. Broadband Connection: A high-speed connection that is always on. Types include:
- DSL (Digital Subscriber Line): Uses existing telephone lines but does not block voice calls. Speeds range from 1 to 100 Mbps.
- Cable: Uses the same coaxial cable as cable television. Provides higher speeds than DSL.
- Fibre Optic: Uses light signals through glass or plastic fibres. Provides the fastest speeds (up to 1 Gbps and beyond).
3. Wireless Connection:
- Wi-Fi: Connects devices to a local network wirelessly within a limited range.
- Mobile Data (3G/4G/5G): Uses cellular networks for internet access on mobile devices.
- Satellite: Uses satellite signals for remote areas where wired connections are not available.
4. Leased Line: A dedicated, always-on connection used by businesses that require guaranteed bandwidth and uptime.
Q3. Explain the structure of an email address.
username@domainname
- Username: The name chosen by the user (or assigned by the organisation). It identifies the specific mailbox. Example: john.doe
- @ symbol: Separates the username from the domain name. It is read as "at."
- Domain name: The name of the email server or organisation that hosts the email service. Example: gmail.com, yahoo.co.in
Example: In [email protected], "student" is the username and "school.edu" is the domain name.
Rules for email addresses:
- The username can contain letters, numbers, dots, hyphens, and underscores.
- The username cannot contain spaces or special characters like ! # $ % ^ & *.
- Email addresses are not case-sensitive ([email protected] is the same as [email protected]).
Q4. Compare POP3 and IMAP protocols.
| Feature | POP3 | IMAP |
|---|---|---|
| Full Form | Post Office Protocol version 3 | Internet Message Access Protocol |
| Purpose | Receiving (downloading) email | Receiving and managing email |
| Server Storage | Downloads email and usually deletes from server | Keeps email on the server; syncs across devices |
| Access | Single device | Multiple devices |
| Speed | Faster for downloading | Requires continuous connection |
| Storage | Saves local storage space | Uses server storage |
| Offline Access | Full access to downloaded emails | Limited offline access |
| Port | 110 | 143 |
| Best For | Users who check email from one device | Users who access email from multiple devices |
POP3 is simpler and works well for single-device access, while IMAP is better for users who need to access the same email account from multiple devices since it keeps everything synchronised on the server.
Q5. What are the advantages of email?
1. Speed: Messages are delivered almost instantly, regardless of the distance between sender and receiver.
2. Cost-effective: Sending an email is free (apart from the internet connection cost), unlike postal mail which requires stamps.
3. Attachments: You can attach files such as documents, images, audio, and video to your email.
4. Multiple Recipients: The same message can be sent to many people simultaneously using the To, Cc, and Bcc fields.
5. Record Keeping: Sent and received emails are stored automatically, providing a written record of communication.
6. Accessibility: Email can be accessed from anywhere in the world using a computer or mobile device with an internet connection.
7. Organisation: Emails can be organised into folders, flagged for follow-up, and searched easily.
8. Environmentally Friendly: Reduces the need for paper compared to traditional postal mail.
IV. Long Answer Questions (5 Marks)
Q1. Explain the working of the internet with a diagram description.
How the Internet Works:
1. Client-Server Model: When you type a URL in your browser (the client), your computer sends a request to a web server. The server processes the request and sends back the requested web page. This is called the client-server model.
2. TCP/IP Protocol Suite: All communication on the internet follows the TCP/IP protocol suite:
- IP (Internet Protocol): Handles addressing and routing of data packets. Each device has a unique IP address.
- TCP (Transmission Control Protocol): Ensures reliable delivery of data by breaking it into packets, sending them, and reassembling them in the correct order.
3. DNS Resolution: When you type a domain name (e.g., www.google.com), the DNS server translates it into the corresponding IP address (e.g., 142.250.80.46) so the request can be routed to the correct server.
4. Data Transmission:
- Your request is broken into small packets.
- Each packet is labelled with the destination IP address.
- Packets travel through multiple routers and networks (the internet backbone) to reach the destination.
- Packets may take different routes and arrive at different times.
- TCP reassembles the packets in the correct order at the destination.
5. HTTP/HTTPS: The browser communicates with the web server using HTTP (HyperText Transfer Protocol) or HTTPS (the secure version). The server sends the HTML page, which the browser renders.
6. The Role of ISPs: Internet Service Providers (ISPs) provide the connection between your device and the internet backbone. Your device connects to the ISP's network, which connects to larger networks and ultimately to the destination server.
Key Components:
- Modem: Converts digital signals to analogue (and vice versa) for transmission over phone/cable lines.
- Router: Directs data packets between networks.
- Server: A powerful computer that hosts websites and services.
- Backbone: High-speed data lines that form the main infrastructure of the internet.
Q2. Explain email in detail — its structure, protocols, and etiquette.
Structure of an Email:
1. To: The primary recipient's email address. This field is mandatory. 2. Cc (Carbon Copy): Additional recipients who receive a copy of the email. All recipients can see each other's addresses. 3. Bcc (Blind Carbon Copy): Recipients listed here receive the email, but their addresses are not visible to other recipients. Used for privacy. 4. Subject: A brief description of the email content. Should be clear and concise. 5. Body: The main content of the email — the message you want to convey. 6. Attachments: Files (documents, images, etc.) attached to the email.
Email Protocols:
1. SMTP (Simple Mail Transfer Protocol):
- Used for sending email from a client to a server and between servers.
- Works on port 25.
- The sending process: Client → SMTP server → Recipient's SMTP server → Recipient's mailbox.
2. POP3 (Post Office Protocol version 3):
- Used for receiving (downloading) email from a server.
- Works on port 110.
- Downloads emails to the local device and typically deletes them from the server.
- Suitable for accessing email from a single device.
3. IMAP (Internet Message Access Protocol):
- Used for receiving and managing email on the server.
- Works on port 143.
- Syncs emails across multiple devices — reading, deleting, or moving an email on one device is reflected on all devices.
- Suitable for users who access email from multiple devices.
Email Etiquette (Netiquette):
1. Use a clear subject line that summarises the email content. 2. Be concise — keep the message brief and to the point. 3. Use proper greetings and sign-offs — address the recipient politely and close with your name. 4. Avoid writing in ALL CAPS — it is interpreted as shouting. 5. Proofread before sending — check for spelling, grammar, and factual errors. 6. Be cautious with humour and sarcasm — tone is difficult to convey in text. 7. Respect privacy — do not share someone's email address without permission. 8. Reply promptly — acknowledge receipt of important emails. 9. Use Bcc for mass emails — to protect recipients' email addresses. 10. Do not send large attachments without confirming the recipient can receive them.
Q3. Describe the various internet services.
1. World Wide Web (WWW): The most popular internet service, allowing users to access websites and web pages using a browser. The web uses HTTP/HTTPS protocol and HTML to display content. It supports text, images, audio, video, and interactive content.
2. Email (Electronic Mail): Allows users to send and receive text messages, documents, and files over the internet. Protocols used include SMTP (sending), POP3, and IMAP (receiving). Examples: Gmail, Yahoo Mail, Outlook.
3. File Transfer Protocol (FTP): Used for uploading and downloading files between a client and a server on the internet. FTP is commonly used by web developers to transfer website files to a web server. It works on ports 20 and 21.
4. Telnet: A protocol that allows a user to log into a remote computer and execute commands as if they were sitting at that computer. It is used for remote administration but is less secure (transmits data in plain text).
5. Instant Messaging and Chat: Real-time text communication between users over the internet. Examples include WhatsApp, Telegram, and Google Chat.
6. Video Conferencing: Allows face-to-face communication over the internet using audio and video. Examples: Zoom, Google Meet, Microsoft Teams.
7. Social Networking: Online platforms that allow users to create profiles, share content, and interact with others. Examples: Facebook, Twitter/X, Instagram, LinkedIn.
8. E-commerce: Buying and selling goods and services over the internet. Examples: Amazon, Flipkart.
9. Online Education: Platforms that provide courses, tutorials, and learning materials over the internet. Examples: NPTEL, Coursera, Khan Academy.
10. Cloud Storage: Storing files on remote servers accessible via the internet. Examples: Google Drive, Dropbox, OneDrive.
11. Voice over IP (VoIP): Making voice calls over the internet instead of traditional phone lines. Examples: Skype, Google Voice.
12. Search Engines: Programs that help users find information on the internet by indexing web pages and returning relevant results. Examples: Google, Bing, Yahoo.
Common Mistakes to Avoid
- Confusing the internet (the network infrastructure) with the World Wide Web (a service on the internet).
- Mixing up SMTP (for sending) with POP3/IMAP (for receiving) — remember: S in SMTP stands for "Sending."
- Writing email addresses with spaces or special characters — only letters, numbers, dots, hyphens, and underscores are allowed in the username.
- Forgetting that HTTPS is the secure version of HTTP — the "S" stands for Secure (SSL/TLS encryption).
- Confusing a domain name (google.com) with a URL (https://www.google.com) — a URL includes the protocol.
- Thinking an IP address and a domain name are the same — DNS translates between them.
- Confusing Cc and Bcc — Cc recipients are visible to all, Bcc recipients are hidden.
- Stating that POP3 stores emails on the server — POP3 typically downloads and deletes from the server; IMAP keeps them on the server.
Exam Checklist
- [ ] Can define internet, WWW, browser, and search engine
- [ ] Know the difference between the internet and the World Wide Web
- [ ] Can explain the structure and parts of a URL
- [ ] Understand the email structure (To, Cc, Bcc, Subject, Body, Attachments)
- [ ] Can differentiate SMTP, POP3, and IMAP protocols
- [ ] Know the types of internet connections (dial-up, broadband, wireless, leased line)
- [ ] Can explain DNS and its role in translating domain names to IP addresses
- [ ] Can list and describe various internet services
- [ ] Understand email etiquette (netiquette)
- [ ] Know the difference between HTTP and HTTPS
- [ ] Can define IP address, domain name, and ISP
- [ ] Understand the client-server model of internet communication
