The once mighty AltaVista was purchased by Yahoo in 2003 and was eventually closed down. It no longer exists. If you try to go there, you will be redirected to Yahoo.
I cut my SEO teeth optimizing websites for AltaVista back before Google existed or Yahoo was popular, when the only way to get to Altavista was to go through the Digital Equipment website. I think the first URL I ever typed into a browser was this one for AltaVista in 1996:
The AltaVista search engine was great for a while, then was made unusable back in its heyday by spammers filling it with spammy results. The spam got so bad we users started looking around for other search engines to use. It was not uncommon to see the entire first page of search results filled with links to pages from the same irrelevant website.
Here's the Wikipedia article on Altavista, which doesn't really do it justice. It could have grown up to become something like Google, but couldn't get itself organized. Sad.