The Internet Basics and HTML

Communication Using the Internet

• Basics of Computer Networks:

  • LAN (Local Area Network): A network covering a small geographic area, such as a home, school, or office, allowing devices to share resources and communicate.
  • WAN (Wide Area Network): A network that spans a large geographic area, such as a city, country, or even the world, connecting multiple LANs.
  • OSI (Open Systems Interconnection) Model: A conceptual framework used to understand network interactions in seven layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application.
  • TCP/IP Model: The suite of communication protocols used to connect network devices on the internet, consisting of four layers: Link, Internet, Transport, and Application.

• Concept of Internet:

  • The Internet is a global network that connects millions of private, public, academic, business, and government networks, allowing the exchange of information and communication across the globe.

• Applications of Internet:

  • Web Browsing, Email, Online Shopping, Social Networking, E-Governance, Streaming Services, and Cloud Computing are some key applications of the internet.

• Connecting to the Internet:

  • ISP (Internet Service Provider): A company that provides access to the internet. Connecting to the internet can be done via various methods such as DSL, fiber optics, cable, and wireless connections.

• WWW and Web Browsers:

  • World Wide Web (WWW): An information system where documents and other web resources are accessed through the internet using web browsers.
  • Web Browsing Software: Tools like Chrome, Firefox, Safari, and Edge that allow users to access and navigate web pages.
  • Search Engines: Programs like Google, Bing, and Yahoo that help users find specific information on the internet.
  • URL (Uniform Resource Locator): The address used to access resources on the web.
  • Domain Name: A human-readable address (like www.example.com) that maps to an IP address.
  • IP Address: A numerical label assigned to each device connected to a network, used to locate and identify devices.

• Communications and Collaboration:

  • Electronic Mail (Email): A method of exchanging digital messages over the internet.
  • Getting an Email Account: Setting up a personal email account using services like Gmail, Yahoo, or Outlook.
  • Sending and Receiving Emails: Involves composing messages, attaching files, and sending them to others via their email addresses.
  • Document Collaboration: Tools like Google Docs and Microsoft Office Online allow multiple users to work on the same document simultaneously.
  • Instant Messaging: Real-time text communication through applications like WhatsApp, Messenger, and Slack.
  • Netiquettes: The code of polite behavior expected in online communication.

---

UNIT 2 – HTML (HyperText Markup Language)

Introduction to HTML

HTML is the standard markup language used to create web pages. It structures the content of a web page using elements defined by tags.

• Key Components of an HTML Document:

  • HTML Elements: The basic building blocks of an HTML document, defined by tags such as <p>, <h1>, and <a>.
  • Tags and Attributes: Tags are the HTML elements, and attributes provide additional information about elements, such as class="example".

• HTML Basic Tags:

  • Headers: <h1> to <h6> tags define headings in descending order of importance.
  • Formatting Tags: Tags like <b>, <i>, and <u> are used for bold, italic, and underline text formatting.
  • Lists:
    • Ordered List (<ol>): A list where items are numbered.
    • Unordered List (<ul>): A list where items are bulleted.
    • Definition List (<dl>): A list of terms and their definitions.

• Nesting of Lists:

  • Combining lists within other lists to create complex list structures.

• Hyperlinks:

  • Created using the <a> tag, allowing navigation from one web page to another or to a different section within the same page.

• Tables:

  • Structured data presentation using <table>, with rows (<tr>) and cells (<td>).

• Images:

  • Added to web pages using the <img> tag, with attributes like src (source) and alt (alternative text).

• Images as Hyperlinks:

  • Using the <a> tag to make an image clickable, directing users to another web page or resource.

• Forms:

  • A way to collect user input using <form>, <input>, <textarea>, <select>, and buttons.

• Frames:

  • Used to divide the browser window into multiple sections, allowing different HTML documents to be displayed simultaneously. Note that frames are deprecated in HTML5.

• Div and Span Tags for Grouping:

  • <div>: A block-level container for grouping elements.
  • <span>: An inline container for styling parts of the text or grouping inline elements.

• Using Object Tag to Embed Multimedia Elements:

  • The <object> tag is used to embed multimedia elements like audio, video, and other applications.

This introduction provides a foundational understanding of internet basics and HTML, essential for web development and effective internet usage.