[lisper]

Google was incorporated in September 1998. They closed their A round in June 1999. AdWords launched in October of 2000, but they were selling ads through sales people for quite a while before that. Selling ads was always the plan from day 1.

[gman83]

Yeah but Larry Page & Sergey Brin developed PageRank in 1996.

[lisper]

Yes, as an academic research project. We can quibble over what it means to be "released", but the main point is that when it came time to try to monetize the technology, it was advertising from day 1. No other revenue-generation model was ever tried, or even seriously considered.