What is the difference between front end and back end web development?

Question

I'm learning HTML, CSS, and JavaScript, and I've seen that there are two types of web development, front end and back end. I was wondering what the difference was, which one HTML, CSS, and JavaScript applied to, and what languages the one uses that those languages don't apply to.

Answer 1

front end
-- only the person will see it.
e.g. layout

back end
-- logic part. user doesn't know what is really happened.
e.g. e-commerce gateway payment calculations