Synetic College Logo
Unit 1 of 4 · M.Sc IT Sem 2

Unit 1: Internet basics and introductory HTML

Web Technologies notes · PTU syllabus (PGCA1909)

3 min read6 topics10 exam questions
On this page
  1. Unit summary
  2. Internet connectivity and the web
  3. IP addressing
  4. TCP/IP overview
  5. HTML tags: paired and singular
  6. Document structure: head, body, titles and footers
  7. Text formatting, heading styles, text styles and colour coding
  8. Key terms
  9. Quick revision
  10. Important questions

Unit summary

The web runs on internet protocols and HTML. This unit covers internet connectivity and IP addressing, an overview of TCP/IP, HTML tags — paired and singular — the document head and body, titles and footers, text formatting, heading styles, text styles and colour coding.

After this unit you can

  • Explain internet connectivity, IP addressing and TCP/IP
  • Use paired and singular HTML tags
  • Structure a document with head, body, title and footer
  • Format text, headings and colours

PTU syllabus topics

  • Internet connectivity and IP addressing
  • TCP/IP overview
  • HTML tags (paired and singular)
  • document head/body
  • title/footer
  • text formatting
  • heading styles
  • text styles and color coding
ComparisonIPv4 vs IPv6
IPv4
IPv6

Address size

32 bits

128 bits

Format

Dotted decimal: 192.168.1.1

Hexadecimal: 2001:db8::1

Addresses

About 4.3 billion

About 3.4 × 10³⁸

Header

Variable, with checksum

Fixed, simpler

1

Topic 1

Internet connectivity and the web

The internet is a global network of interconnected computer networks that communicate using the TCP/IP protocols. The World Wide Web (WWW) is a service on the internet made of linked web pages accessed through HTTP/HTTPS.

ProcessHow a web page reaches you
  1. 1Type a URL

    https://www.sbs.ac.in

  2. 2DNS lookup

    Domain name translated to an IP address

  3. 3Request

    Browser sends an HTTP request to the web server

  4. 4Response

    Server sends back HTML, CSS, JS and images

  5. 5Render

    Browser displays the page

  • Domain name: a readable address (sbs.ac.in). Top-level domains include .com, .org, .edu, .in, .ac.in.
  • Connectivity: dial-up (old), broadband, fibre, mobile data (4G/5G) and Wi-Fi, provided by an ISP (Internet Service Provider).
  • Web browser (Chrome, Firefox, Edge) requests and displays pages; a web server stores and serves them.
ProcessRequest–response cycle
  1. 1

    User enters a URL

  2. 2

    DNS resolves the domain to an IP address

  3. 3

    Browser sends an HTTP request

  4. 4

    Web server (Apache, Nginx, IIS) processes it

  5. 5

    Server returns an HTTP response with HTML

  6. 6

    Browser renders the page and requests images, CSS and scripts

2

Topic 2

IP addressing

  • Every device on the internet has an IP address. IPv4 uses 32 bits written as four decimal numbers (192.168.1.10); IPv6 uses 128 bits written in hexadecimal groups (2001:db8::1) because IPv4 addresses ran out.
ComparisonTypes of IP addresses
Meaning
Example

Public

Globally unique, reachable on the internet

Address assigned by the ISP to a router

Private

Used inside local networks; translated by NAT

10.x.x.x, 172.16–31.x.x, 192.168.x.x

Static

Fixed, set manually

Web servers

Dynamic

Assigned automatically by DHCP

Laptops and phones

  • Domain Name System (DNS): translates names such as www.sbs.ac.in into IP addresses.
3

Topic 3

TCP/IP overview

HierarchyTCP/IP layers
  1. Application

    HTTP, HTTPS, FTP, SMTP, DNS — services for users

  2. Transport

    TCP (reliable, connection-oriented) and UDP (fast, connectionless)

  3. Internet

    IP addressing and routing; ICMP

  4. Network access

    Ethernet, Wi-Fi — physical delivery of frames

  • A web request uses HTTP over TCP over IP: TCP splits data into segments, IP routes packets across networks, and the receiver reassembles them.
4

Topic 4

HTML tags: paired and singular

HTML (HyperText Markup Language) describes the structure of a web page using tags in angle brackets.

ComparisonPaired vs singular tags
Paired (container) tags
Singular (empty) tags

Structure

Opening and closing tag

Only one tag

Content

Wraps content

No content

Examples

<p>…</p>, <b>…</b>, <h1>…</h1>

<br>, <hr>, <img>

Attributes give extra information inside the opening tag: <img src="logo.png" alt="SBS logo">.

5

Topic 5

Document structure: head, body, titles and footers

html<!DOCTYPE html>
<html>
  <head>
    <title>My First Page</title>
  </head>
  <body>
    <h1>Welcome to SBS</h1>
    <p>This is a paragraph.</p>
    <footer>Copyright 2026</footer>
  </body>
</html>
  • <head> holds information about the page (title, meta tags, CSS links) — not shown in the page body.
  • <title> appears on the browser tab.
  • <body> holds everything visible on the page.
  • Footer: the footer element (or a final section) holds copyright, contact and links, e.g. a footer with "© 2026 SBS".
6

Topic 6

Text formatting, heading styles, text styles and colour coding

TagEffect
<h1> to <h6>Headings, largest to smallest
<p>Paragraph
<br> / <hr>Line break / horizontal rule
<b> or <strong>Bold (strong also means importance)
<i> or <em>Italic (em also means emphasis)
<u>Underline
<sup> / <sub>Superscript / subscript
<pre>Preformatted text (keeps spaces)

Colours can be written as names (red), hexadecimal codes (#FF0000) or RGB values (rgb(255, 0, 0)). In modern HTML they are applied with CSS: <p style="color:#0b6b3a">Green text</p>.

Exam tip

Hex colour codes use pairs for red, green and blue from 00 to FF: #000000 is black and #FFFFFF is white.

  • Colour coding: colours are given by name (red), hexadecimal #RRGGBB (#1E3A8A), rgb(30, 58, 138) or hsl(); in old HTML through the color and bgcolor attributes, today through CSS (color, background-color).

Key terms

IP address
Numeric address identifying a device on a network
DNS
System translating domain names to IP addresses
Paired tag
Tag with an opening and a closing part
Singular tag
Empty tag without a closing part, such as br or img
Hex colour code
Colour written as #RRGGBB

Quick revision

  • ISP, broadband, Wi-Fi, mobile data; URL → DNS → HTTP request → response.
  • IPv4 (32 bits) and IPv6 (128 bits); public, private, static, dynamic; DNS.
  • TCP/IP layers; TCP vs UDP.
  • Paired and singular tags; html, head, title, body, footer.
  • Headings h1–h6; b, i, u, strong, em; colour names, hex and rgb.

Important exam questions

Practice questions written to the PTU exam pattern for this unit's syllabus: short answers (Section A style) and long answers (Sections B and C style).

Short-answer questions

  1. Q1.What is an IP address?
  2. Q2.Distinguish IPv4 and IPv6.
  3. Q3.Name the layers of TCP/IP.
  4. Q4.Distinguish paired and singular tags with examples.
  5. Q5.What is placed in the head section?
  6. Q6.Write the hex code for pure red.

Long-answer questions

  1. Q1.Explain internet connectivity, IP addressing and DNS.
  2. Q2.Give an overview of the TCP/IP protocol suite.
  3. Q3.Explain the structure of an HTML document.
  4. Q4.Explain text formatting and colour coding in HTML.

Stuck on this unit?

Message SBS on WhatsApp for help with Web Technologies, or to ask about studying M.Sc IT at Synetic.

WhatsApp us