Browsers and Searching the Internet

What is a "browser"
What can you do with a browser?
Where do you get a browser from?
What different brands of browsers exist?
How would you navigate in a browser, what is the meaning of the buttons on the top?
What is a webpage, what is a link?
(What is a plug-in?)
How do you get information on a specific topic on the internet?
"Google" is a well-known search engine. What does it mean?
How does a search engine work?
Why is "Google" nowadays so popular?
If your Google search was not successful, what else could you do?
What is a internet directory?
What is the open directory, and how does it work?
Is everything you find on the internet true or of high quality?