HTML CSS Attributes:

ID #

class .

(Other HTML Core Attributes: title and style)

But we also have Pseudo-Class based on characteristics rather than name, in CSS we use a : to signify the pseudo-class.

CSS2

:focus has focus

:hover rollover

:active active element (:link)

Original CSS

:link, :visited, and :unvisited

Pseudo Elements: :first-letter, :first-line, :first-child :before and :after