The front end of a website (or web or mobile application) is the part a user sees and directly interacts with. The front end is built with languages like:
HTML (HyperText Markup Language) is the backbone of the Web. Every website you visit is built with HTML. It takes care of all the structure and content. HTML5 is the current iteration of HTML on the Web, although sites built with older versions still run fine in your browser.
CSS (Cascading Style Sheets) is what controls the way the HTML looks on the page. CSS sets the colors, fonts, background images, and even the way the page is laid out (you can use CSS to arrange the HTML elements on a page however you want, even if it’s different than the order they’re arranged in the HTML file). CSS3 is the current iteration of CSS on the Web, and it adds a ton of features for things like basic interactivity and animations.
It’s the Internet, what can we say!