The Basics Of Coding For Web Design

A quick look at web languages, as I understand them (note the caveat):

HTML is a markup language that provides site structure by annotating elements in a hierarchical manner – the building blocks of the site.
CSS is a coding language that provides instruction to browsers as to how to shape, style and display HTML elements.
Javascript is a programming language that adds interactivity to websites, allowing them to respond to visitors’ actions.

All three of these determine the front end of the website, which the user (browser) sees and interacts with, and are contained in the back end as well.