Google Inc. on Wednesday fired another salvo aimed at maintaining the lead in Internet search while making its software more accessible outside Web browsers in its ongoing duel with rivals Microsoft Corp. and Yahoo Inc.

The company is adding a new tool to make it easier to share information through its online search engine and enabling users to download mini-applications, or "widgets," designed to become fixtures on a computer screen.

Google also said it's planning to introduce an online notebook for its users to paste and save search engine results.

The notebook, to be displayed as a small window in the right hand corner of a computer screen, won't be available until next week.

Google launched the other new products Wednesday in an effort to impress more than 100 reporters invited to the company's Silicon Valley headquarters to meet with the search engine's top executives.

The information-sharing feature, known as "Google Co-op," marks the Mountain View, Calif.-based company's first foray into "social search" — a niche that has been a Yahoo focal point.

With the co-op service, users with a personal Google login will be able to label, Web pages so the information can be easily found by other people, including friends, family and co-workers.

The co-op feature also allows users to alert Google about their specific interests, like movies, restaurants and celebrity gossip, so information related to those topics appears near the top of the results page whenever they make a relevant search request.

Sunnyvale, Calif.-based Yahoo has been developing more social search features as a way to differentiate itself in its pursuit of Google, which has become more profitable than its older rival.

In recent months, though, Google has widened its lead over both Yahoo and Microsoft — an advantage the company hopes to expand even further by making a "heavy, heavy investment in new search algorithms," CEO Eric Schmidt told reporters Wednesday. He didn't provide specifics.

Google's ambitions extend beyond the Web browser. Toward that end, Google unveiled its latest upgrade to its search engine for finding information stored on computer hard drives.

The improvements include a toolbox of so-called widget software that display snapshots of vital information, such as stock prices and weather, without a Web browser.

The widgets, which Google calls "gadgets," show up as colorful icons on the computer desktop — an area long dominated by Microsoft, the world's largest software maker.

Both Google and Microsoft have been spending billions to top one another in a battle that is expected to escalate during the next few years as they battle for high-tech supremacy.

"I do believe the winner will be the fastest innovator who partners most broadly," said Schmidt, who added he still sees "limitless growth" opportunities for Google.

Google is playing catch up with its gadgets. A small startup called Konfabulator first introduced the widget concept for Apple Computer Inc.'s Macintosh in 2002. Yahoo embraced widgets last year when it bought Konfabulator for an undisclosed amount.

Using Google's gadgets requires installing the company's desktop search software, which was introduced in 2004. Wednesday's upgrade represents the fourth version of Google's desktop search.