I think yahoo is/was sending off search results to Bing. A long time ago they used to send them to Google. Before that they would refer to themselves as a web

I think yahoo is/was sending off search results to Bing. A long time ago they used to send them to Google. Before that they would refer to themselves as a web directory, not a search engine. And WAYY before that every result page had a link to search on different sites, web crawler, lycos, maybe even google my memory is kind of fuzzy. The point is that Yahoo cares more about getting people to their portal, not so much what technology it happens to be using.