Descendant selectors are used to select elements that are descendants of another element in the document tree.

For example, you may wish to target a specific <em> element on the page, but not all <em> elements. A sample document could contain the following code:

If you use a type selector like the example below, you will select all <em> elements on the page:

However, if you use a descendant selector, you can refine the <em> elements that you select. The rule below will only select <em> elements that are descendants of <p> elements. If this rule is applied, the <em> element within the <h1> will not be colored blue.

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