HTML Tags

Now that you know how to peer into existing HTML files and how to create your own, the next step is to understand what goes inside the average HTML file. It all revolves around a single concept—tags.

HTML tags are formatting instructions that tell a browser how to transform ordinary text into something visually appealing. If you were to take all the tags out of an HTML document, the resulting page would consist of nothing more than plain, unformatted text.

What’s in a Tag

You can recognize a tag by looking for angle brackets, two special characters that look like this: < >. To create a tag, you type HTML code between the brackets. This code is for the browser’s eyes only; web visitors never see it (unless they use the View→Source trick to peek at the HTML). Essentially, the code is an instruction that conveys information to the browser about how to format the text that follows.

For example, one simple tag is the <b> tag, which stands for “bold” (tag names are always lowercase). When a browser encounters this tag, it switches on boldface formatting, which affects all the text that follows the tag. Here’s an example:

This text isn't bold. <b>This text is bold.

On its own, the <b> tag isn’t quite good enough; it’s known as a start tag, which means it switches on some effect (in this case, bold lettering). Most start tags are paired with a matching end tag that switches off the effect.

You can easily recognize an end tag. They look the same as start tags, except that they begin with ...

Get Creating a Website: The Missing Manual, 3rd Edition now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.