Web browsers

The essentials

A web browser is software used to find, open and display web pages. It sends a request to a web server using the page's URL and shows the HTML response. Common browsers include Google Chrome, Mozilla Firefox, Microsoft Edge, Apple Safari and Opera. Mosaic was one of the early popular graphical browsers.

Key points

• Browser settings let users choose the home page and default search engine, manage saved passwords, set privacy and security options, block pop-ups, and clear history and cache.
• Private or incognito browsing does not save history, cookies or form data on the device after the window is closed. It does not hide activity from the website or the network provider.
• Add-on (extension): a small program that adds a new feature to the browser itself, such as an ad blocker, a dictionary or a password manager.
• Plug-in: a program that helps the browser display or run particular content it cannot handle on its own, such as a certain video or document format. Modern browsers handle most content without plug-ins.
• Cookie: a small text file that a website stores on the user's computer through the browser. It remembers information such as login status, preferences or items in a shopping cart. Cookies are not programs and cannot run, but third-party cookies can be used to track browsing across sites, raising privacy concerns.
• Users can block or delete cookies from browser settings.

Exam tips

• Extension = adds functions to the browser; plug-in = handles specific content.
• Know what a cookie stores and why it can be a privacy issue.

Common mistakes

• Thinking a cookie is a virus. It is a text file, though it can be misused for tracking.
• Thinking incognito mode makes a user anonymous on the Internet.