Google's 'Hummingbird' hatches new search

Google has quietly retooled the closely guarded formula running its internet search engine to give better answers to the increasingly complex questions posed by web surfers.

The overhaul came as part of an update called Hummingbird, which Google has gradually rolled out in the past month without disclosing the modifications.

The changes could have a major impact on traffic to websites.

Hummingbird represents the most dramatic alteration to Google's search engine since it revised the way it indexes websites three years ago as part of a redesign called Caffeine, according to Amit Singhal, a senior vice president for the company.

He estimates the redesign will affect the analysis of about 90 per cent of the search requests that Google gets.

Any reshuffling of Google's search rankings can have sweeping ramifications because they steer so much of the internet's traffic.

Google fields about two of out every three search requests in the US and handles an even larger volume in some parts of Europe. The changes could also drive up the price of Google ads tied to search requests if websites whose rankings are demoted under the new system feel they have to buy the marketing messages to attract traffic.

The search ads and other commercial pitches related to web content account for most of Google's revenue, which is expected to approach $US60 billion ($A64.42 billion) this year.

Google disclosed the existence of the new search formula on Thursday at an event in the Menlo Park, California, garage where CEO Larry Page and fellow co-founder Sergey Brin started the company 15 years ago.

Hummingbird is aimed at giving Google's search engine a better grasp at understanding concepts instead of mere words, Singhal said.

The change was needed, Singhal said, because people have become so reliant on Google that they now routinely enter lengthy questions into the search box instead of just a few words.