Google is now relying on artificial intelligence, with a system dubbed RankBrain, for a small but significant part of its search business. Since Google is identified with search, keeping on the bleeding edge of search technology is critical to its dominance, and Google has been researching artificial intelligence — software that learns about the world — for over five years. Prior to launching RankBrain for search, Google has been a big corporate sponsor of AI, invested in it for videos, speech and translation.

According to Bloomberg, Google senior research scientist Greg Corrado described how artificial intelligence works by embedding written language into mathematical vectors that the computer can understand. That makes RankBrain particularly adept at handling unfamiliar or ambiguous queries. As a result, Google is currently using RankBrain to deal with 15 percent of daily queries.

RankBrain works differently than the rest of Google’s search technologies, says Corrado. “The other signals, they’re all based on discoveries and insights that people in information retrieval have had, but there’s no learning,” he said.

Since its deployment, RankBrain is now the third-most important signal contributing to the result of a search query, reports Corrado, who notes that the AI debut has “gone better than we would have expected.” Google is now attempting to embed AI into every aspect of its business, says Google chief executive Sundar Pichai. “Machine learning is a core transformative way by which we are rethinking everything we are doing,” he says.

In a test, Google search engineers were asked to look at some pages and guess which they thought Google’s search engine technology would rank on top. RankBrain had an 80 percent success rate, 10 points over the humans. Google isn’t the only company deploying AI; Facebook uses it to filter the news feed for personalized homepages and Microsoft uses it for its Bing search engine.