This change is as momentous as the industrial-age shift from craft production to mass manufacture, from individual workers in separate shops turning out finished products step by step to massive factories that break up production into thousands of parts and perform them simultaneously. No single computer could update millions of auctions in real time, as eBay does, and no one machine could track thousands of stock portfolios made up of offerings on all the world’s exchanges, as Yahoo does. And those are, at most, terascale tasks. Page and Brin understood that with clever software, scores of thousands of cheap computers working in parallel could perform petascale tasks – like searching everything Yahoo, eBay, Amazon.com, and anyone else could shovel onto the Net. Google appears to have attained one of the holy grails of computer science: a scalable massively parallel architecture that can readily accommodate diverse software.
Google’s core activity remains Web search. Having built a petascale search machine, though, the question naturally arose: What else could it do? Google’s answer: just about anything. Thus the company’s expanding portfolio of Web services: delivering ads (AdSense, AdWords), maps (Google Maps), videos (Google Video), scheduling (Google Calendar), transactions (Google Checkout), email (Gmail), and productivity software (Writely). The other heavyweights have followed suit.