The good news is that if you've gotten this far (that is, to the Codecademy website), you've met HTTP before! It's that little bit before the "www" in a website's address. Some browsers might hide it from you, but Codecademy's full address is:
The HTTP stands for HyperText Transfer Protocol. HyperText is text with links in it (like this!) and a transfer protocol is a fancy way of saying "rules for getting something from one place to another." In this case, the rules are for transferring web pages to your browser.