3.5 Given a scenario, configure and use web browsers.
📘CompTIA ITF+ (FC0-U61)
1. What is a Cache?
A cache is a storage area on your computer where your web browser saves copies of files from websites you visit. These files can include:
- HTML pages (the main content of a website)
- Images (like logos or pictures)
- CSS and JavaScript files (make the site look and work properly)
Purpose of a cache:
- Speed up browsing: When you revisit a website, your browser can load it from the cache instead of downloading all the files again.
- Reduce bandwidth use: Saves internet data because repeated files are not downloaded every time.
Example in IT terms:
- If an employee visits an internal company portal multiple times a day, the portal’s logo and menu layout may be loaded from the cache instead of downloading every time. This makes the site load faster.
2. How Caching Works
- You visit a website.
- The browser downloads files from the web server and stores them in the cache.
- The next time you visit the same page, the browser checks if it already has those files.
- If the files are still valid, it loads them from the cache instead of downloading again.
- If the files have changed, it downloads the new versions from the server.
Key point for exams:
- Cached files are temporary. Browsers manage them automatically, but sometimes old cached files can cause problems (like outdated website content).
Clearing Cache
1. Why Clear Cache?
You might need to clear your cache in situations like:
- Website updates not showing: The browser is still using old cached files.
- Troubleshooting browser problems: Slow loading, broken layouts, or errors may be caused by corrupted cache files.
- Security and privacy: Cached data may store sensitive information (like login pages) that you don’t want stored.
2. How to Clear Cache
Most web browsers have a similar method to clear the cache. Here’s a general IT-focused guide:
Steps:
- Open your browser settings or options menu.
- Look for Privacy & Security or History section.
- Find Clear Browsing Data (Chrome, Edge) or Clear Recent History (Firefox).
- Choose Cached images and files (you can also choose to clear cookies and history if needed).
- Click Clear/OK.
Shortcut:
- In Chrome, Edge, and Firefox, pressing Ctrl + Shift + Delete opens the clear cache menu.
3. Effects of Clearing Cache
- Website files will be downloaded again on your next visit.
- This may make the first load slightly slower but ensures you see the latest version of the site.
- Helps solve display issues or errors caused by outdated cached files.
Example in IT environment:
- An IT admin updates the company’s intranet portal. Employees clear their browser cache to see the latest version with the new menus and forms correctly.
Exam Tip
- Know the difference between cache and cookies.
- Cache stores files to make websites load faster.
- Cookies store user-specific data like login info or site preferences.
- Know how to clear cache in common browsers. This is often a scenario question.
✅ Summary for Students
- Cache: Temporary storage for website files to speed up browsing.
- Clearing Cache: Removes stored files to fix issues, see updated content, or improve security.
- Where to do it: Browser settings → Privacy/Security → Clear browsing data → Select cache.
