HTML stands for Hypertext Markup Language. According to MDN, HTML is “the code that is used to structure a web page and its content.” Content in this case could mean headings, paragraphs of text, lists, images, and videos, among other things.
Here’s a sample of some HTML code:
<h1>Grocery List</h1> <p>Below is a list of things I need to buy today.</p> <ul> <li>Milk</li> <li>Eggs</li> <li>Bread</li> </ul>
We won’t go into what everything in that snippet of code means just yet, but you might be able to tell that the document has a certain structure to it. There might be some symbols that are foreign to you, but hopefully you can see that there is a title, a sentence, and a list in the snippet. The extra symbols you see are identifying those different sections of the document so the browser can render them properly. That’s the power of HTML.
HTML is usually the first language a developer learns when getting into web development. It’s important to learn because every web page you view in the browser uses HTML. There might be other languages or tools involved in piecing together the web page on the server (like PHP, a different programming language), but the end result is always an HTML file that the browser can render.
With just HTML, you can build a multi-page website with structured content. A website made only with HTML code will look very plain in the browser, however. To style the site and make it look nicer, you’ll need to use a different language called CSS. You can learn more about CSS by clicking here (but you should read the HTML articles first if you’re unfamiliar with it).
HTML basics on MDN