Informatics Practices

Web Browsers | Browser Settings, Add-ons, Plug-ins & Cookies | Complete Notes | CBSE Class 12 Informatics Practices (2026–27)

Class 12 · Informatics Practices

Web Browsers | Browser Settings, Add-ons, Plug-ins & Cookies

A web browser is one of the most commonly used software applications on computers and smartphones. It enables users to access websites, search for information, watch videos, use online applications, and communicate over the Internet.

Modern web browsers provide several useful features such as bookmarks, browsing history, downloads, extensions, private browsing, and security settings to improve the browsing experience.


What is a Web Browser?

Definition

A Web Browser is a software application used to access, retrieve, display, and interact with web pages and websites available on the Internet.


How Does a Web Browser Work?

User
   │
Types URL
   │
Browser
   │
Internet
   │
Web Server
   │
HTML/CSS/Images
   │
Browser Displays Webpage

When a user enters a URL, the browser sends a request to the web server. The server returns the webpage files, and the browser interprets them to display the webpage.


Popular Web Browsers

Browser Developer Main Features
Google Chrome Google Fast, secure, supports many extensions
Microsoft Edge Microsoft Integrated with Windows, efficient performance
Mozilla Firefox Mozilla Foundation Open source, privacy-focused
Apple Safari Apple Optimized for macOS and iOS devices
Opera Opera Software Built-in VPN, ad blocker, battery saver

Common Features of a Web Browser

  • Address Bar (URL Bar)
  • Navigation Buttons (Back, Forward, Refresh)
  • Tabs
  • Bookmarks
  • Downloads
  • Browsing History
  • Password Manager
  • Private/Incognito Browsing

Browser Settings

Browser settings allow users to customize security, privacy, appearance, downloads, notifications, and other browsing preferences.

Common Browser Settings

Setting Purpose
Homepage Sets the page that opens when the browser starts.
Search Engine Chooses the default search engine.
Downloads Changes the download location.
Privacy Controls cookies, tracking, and permissions.
Security Protects users from unsafe websites.
Notifications Allows or blocks website notifications.

Bookmarks

A Bookmark is a saved shortcut to a webpage. It helps users quickly revisit frequently used websites without typing the URL again.

Example: Saving the CBSE website or CodeStep Academy homepage as a bookmark.


Browsing History

The browser automatically records the list of websites visited by the user. This record is called Browsing History.

History helps users reopen previously visited webpages but may also reveal browsing activity to others using the same device.


Downloads

Browsers allow users to download files such as PDFs, images, videos, software, and documents from websites. Downloaded files are usually stored in the computer's default Downloads folder unless changed in browser settings.


Add-ons and Extensions

Definition

Add-ons or Extensions are small software components that add new features or enhance the functionality of a web browser.

Examples

  • Ad Blockers
  • Grammar Checkers
  • Password Managers
  • Dark Mode Extensions
  • Language Translators

Advantages

  • Improves productivity.
  • Adds new browser features.
  • Enhances security and privacy.
  • Customizes browsing experience.

Plug-ins

Definition

A Plug-in is a software component that enables the browser to display or handle specific types of content that it cannot process on its own.

In the past, plug-ins such as Adobe Flash Player and Java Plug-in were widely used. Modern browsers now support most web technologies directly, so plug-ins are used much less frequently.


Difference Between Add-ons and Plug-ins

Add-ons / Extensions Plug-ins
Add new browser features. Enable support for specific content or technologies.
Installed from browser stores. Often installed separately.
Improve user experience. Provide functionality not built into the browser.
Example: Ad blocker Example: Adobe Flash Player (legacy)

Cookies

Definition

Cookies are small text files stored by a website in the user's browser. They help websites remember user preferences, login information, and browsing activity.

Uses of Cookies

  • Remember login details.
  • Save language preferences.
  • Store shopping cart items.
  • Personalize website content.

Advantages

  • Faster login.
  • Improved user experience.
  • Personalized browsing.

Disadvantages

  • May reduce privacy.
  • Can be used for tracking user activity.

Browser Cache

The Cache is temporary storage used by browsers to save images, web pages, and other files. Cached files allow frequently visited websites to load faster because the browser does not need to download the same resources again.


Private / Incognito Browsing

Private or Incognito mode allows users to browse without saving browsing history, cookies, or temporary files on the local device after the session ends. However, it does not make users anonymous to websites, Internet Service Providers (ISPs), or network administrators.


Real-Life Applications

Feature Application
Bookmarks Save frequently visited educational websites.
Cookies Remember login credentials.
Extensions Improve productivity and browsing experience.
Downloads Download notes, assignments, and software.
Incognito Mode Browse without saving local history.

Common Errors

Mistake Correct Concept
Browser and Search Engine are the same. A browser displays websites, while a search engine helps users find information on the web.
Cookies are always harmful. Most cookies improve user experience, although some may be used for tracking.
Incognito mode hides users from everyone. It only prevents local storage of browsing history and cookies after the session ends.
Extensions and Plug-ins are identical. Extensions add browser features, while plug-ins provide support for specific content or technologies.

Quick Revision

Concept Remember
Web Browser Software used to access websites
Bookmarks Saved webpage shortcuts
Extensions Add browser features
Plug-ins Support specific content (legacy use)
Cookies Store user preferences and session data
Cache Temporary files for faster loading
Incognito Mode Does not save local browsing history after the session

CBSE Exam Tips

  • A web browser is software used to access websites and web applications.
  • Do not confuse a web browser with a search engine. Examples of browsers include Google Chrome, Microsoft Edge, Mozilla Firefox, Safari, and Opera.
  • Cookies remember user preferences and login information.
  • Extensions add new features to a browser, while plug-ins provide support for specific technologies.
  • Incognito mode does not make Internet browsing completely anonymous; it only prevents local browsing data from being stored after the session ends.

Summary

Web browsers are essential software applications that allow users to access and interact with websites on the Internet. Modern browsers include features such as bookmarks, downloads, browsing history, extensions, cookies, cache management, and private browsing to improve usability and security. Understanding these concepts helps users browse the Internet efficiently and safely and is an important part of the CBSE Class 12 Informatics Practices syllabus.