If you look at code for a lot of other sites, you might come across a number of strange markup styles, including attribute values without quotes. This is permitted in certain circumstances, but it can also break your markup in other circumstances. The element in the code snippet below, , is called an anchor. Anchors enclose text and turn them into links. The href attribute specifies the web address the link points to. You can write this basic version below with only the href attribute, like this:

Anchors can also have a title attribute, a description of the linked page. However, as soon as we add the title in the same fashion as the href attribute there are problems:

As written above, the browser misinterprets the markup, mistaking the title attribute for three attributes: a title attribute with the value The, and two Boolean attributes, Mozilla and homepage. Obviously, this is not intended! It will cause errors or unexpected behavior, as you can see in the live example below. Try hovering over the link to view the title text!

Always include the attribute quotes. It avoids such problems, and results in more readable code.