What is a Web Browser?
The most simple explanation?
A Web browser is computer software that you use to connect to and surf the Internet. It takes you from website to website and it displays the pages for you.
Not all Web browsers are the same.
Mozilla Firefox is the World's most customizable web browser that offers the safest, most fun, and most efficient way to surf and interact with the Internet.
Firefox is free. Updates are free as well. And there are thousands of free add-ons available for it.
Learn more about web browsers on Wikipedia