Yahoo had three search engines when I was there. Inktomi, FAST and Altavista. I came to Yahoo through the acquisition of FAST's web search business, and we ha

Yahoo had three search engines when I was there. Inktomi, FAST and Altavista. I came to Yahoo through the acquisition of FAST's web search business, and we had a variant of page rank which was developed some time in the summer/fall of 1999. I shared an office with the guy who wrote it. After the initial implementation it went through lots of evolution. As did everything in search. What gets people confused is that they tend to think this was the only mechanism in use and that it was a solution that never evolved. Things also get confused by the fact that not everybody knew everything. (For instance, hardly anything in the "official" origin story of FAST is true, and you'll get conflicting stories depending on who you ask). I don't think the Altavista engine was ever used. I think the people from Altavista ended up on Panama, Vespa and possibly some on the Inktomi-based engine. The FAST and Inktomi engines were both in use for a short while for web search, and then the effort was split so the FAST engine was used in what became Vespa (where pagerank isn't as good a mechanism as for the web). Vespa grew out of work at FAST that started around 2002-2003 to separate out the more infrastructural bits of the search engine into more reusable infrastructure components). Eventually Inktomi was used for web search at Yahoo. Simply because of geography (well, politics). Since Inktomi didn't really have anywhere to go that pretty much sealed the fate of Yahoo as maker of a web search. You might be thinking of Inktomi.