CSS differing link styling

From what I know using something like:

.class a {}

Is the same as using:

.class a:link {}

Right?

Additionally..... are the following two styles the same?

.class a:focus {}
.class a:hover {}

Lastly..... the following styling is the color it is when the mouse is down right?

.class a:active {}开发者_开发知识库

• a is every anchor element.
• a:link is only when the hyperlink has never been visited.
• a:focus is when you're tabbing through the page with a keyboard.
• a:hover is when your mouse is over the link.
• a:active is when you mousedown the link.
• a:visited is when you've already visited that link.

• :link = Only links you haven't already visited
• :visited = Links you have already visited
• :focus = For elements in focus, like when you use the tabulator
• :hover = When you move your mouse over it
• :active = for just clicked links