Understanding selectors

The basic building blocks of a cascading style sheet are its style rules. Selectors are used to "select" elements on an HTML page so that they can be styled. Without selectors, there would be no way to determine how the rules should be applied. This topic introduces the fundamentals of cascading style sheet declaration syntax, to describe how selectors are used.

For more information, see the following topics:

• Style rules

• Document tree

• Selectors

• Pseudo-classes and pseudo-elements

• Cascading order and specificity