The new technology, dubbed Google Instant, can shave two seconds to five seconds off every internet search, Google said yesterday, and could entice users to search more on its website.

And with competition increasing from internet rivals such as Microsoft, Yahoo and Facebook, the technology gives Google new ammunition to tout its advantages to web surfers and online advertisers.

"To our knowledge no one has provided search-as-you-type to their users," said Marissa Mayer, Google's vice president of search and user experience, on the sidelines of an event announcing the product at San Francisco's Museum of Modern Art.

During a presentation unveiling Google Instant, Mayer compared the new technology to an automobile's power steering.

"Once you get used to it, it's very tough to go back," said Mayer, though she acknowledged that in testing, certain users had opted to switch off the new feature.

The new technology means Google's search engine can serve up a local weather forecast as soon as a user types the letter "W" in the search box, for instance. If the user continues typing a word other than "weather" into the search box, the results on the page instantly refresh and change accordingly.

Google already offered a feature that suggested popular search queries as a user typed a word in the search box, but the new feature actually delivers a complete page of search results as a search term is being typed.

Analysts said the new technology could help Google, the world's No. 1 search engine, further increase its market share.

Stifel Nicolaus analyst Jordan Rohan called Google Instant a "potential game changer" that competitors will have a hard time replicating, in a note to investors on Wednesday.

Google is facing increased competition from Microsoft's Bing search engine, which recently signed a search partnership with Yahoo.

New technologies, such as the specialized applications that run on Apple's iPhones and fast-growing social networking services such as Facebook, are also threatening to undermine Google's position as the main gateway to online information, according to analysts.