Review

1. CSS can change the look of HTML elements. In order to do this, CSS must select HTML elements, then apply styles to them.

2. CSS can select HTML elements by tag, class, or ID.

3. Multiple CSS classes can be applied to one HTML element.

4. Classes can be reusable, while IDs can only be used once.

5. IDs are more specific than classes, and classes are more specific than tags. That means IDs will override any styles from a class, and classes will override any styles from a tag selector.

6. Multiple selectors can be chained together to select an element. This raises the specificity, but can be necessary.

7. Nested elements can be selected by separating selectors with a space.

8. Multiple unrelated selectors can receive the same styles by separating the selector names with commas.