"Viewing websites from an earlier date"

I believe someone posted this before but I can't find it. It's a website where if you typed in another website's page, you would be able to go to the last date that the website was up before it went down, and navigate it.

Trying to find a video on a forum but the forum went down and doesn't seem to be going back up :[

http://www.archive.org/web/web.php