When you view a simple website, such as this one, you’re really reading a file stored on a computer. Typically, these files are written in a language called HTML: Hypertext Markup Language. HTML is a language that describes the structure and content of a web page. Web browsers know how to interpret read HTML and display it in a user-friendly way.

An example of HTML
An excerpt of the HTML for an early version of this page

A file written in HTML is simply called an “HTML file”. Interpreting HTML files, and turning it into readable text and images, is one of the primary things your web browser does. In fact, your browser will interpret any HTML file you give it, whether it’s on the Internet or right on your own computer.

Is that really all a website is?

It can be – a single HTML file is enough to make a valid website. But these days, most websites are more complex than that. In addition to HTML, there are a couple of other components you’ll typically find on a modern website. I’m not going to explain these in detail, but it’s helpful to know they exist.

Cascading Style Sheets (CSS). If HTML describes the structure and content of a web page, CSS describes its formatting. CSS is added to most web pages to make them look better.

JavaScript. JavaScript is a programming language that can enable a web page to do much more than just show text and images. With JavaScript, web pages can become dynamic and even fully interactive. Some web pages do so much with JavaScript that they’ve become full-blown applications in their own right.