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Google is giving its tried-and-true web-search formula a makeover as it tries to fix the shortcomings of today's technology and maintain its dominant market share.

Over the next few months, Google's search engine will begin spitting out more than a list of blue web links. It will also present more facts and direct answers to queries at the top of the search-results page.

The changes to search are among the biggest in the company's history and could affect millions of websites that rely on Google's current page-ranking results. At the same time, they could give Google more ways to serve up advertisements.

Google isn't replacing its current keyword-search system, which determines the importance of a website based on the words it contains, how often other sites link to it, and dozens of other measures. Rather, the company is aiming to provide more relevant results by incorporating technology called "semantic search," which refers to the process of understanding the actual meaning of words.

Amit Singhal, a top Google search executive, said in a recent interview that the search engine will better match search queries with a database containing hundreds of millions of "entities" -- people, places and things -- which the company has quietly amassed in the past two years. Semantic search can help associate different words with one another, such as a company (Google) with its founders (Larry Page and Sergey Brin).

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Google search will look more like "how humans understand the world," Singhal said, noting that for many searches today, "we cross our fingers and hope there's a web page out there with the answer." Some major changes will show up in the coming months, people familiar with the initiative said, but Singhal said Google is undergoing a years-long process to enter the "next generation of search."

Under the shift, people who search for "Lake Tahoe" will see key "attributes" that the search engine knows about the lake, such as its location, altitude, average temperature or salt content. In contrast, those who search for "Lake Tahoe" today would get only links to the lake's visitor bureau website, its dedicated page on Wikipedia.com, and a link to a relevant map.

For a more complex question such as, "What are the 10 largest lakes in California?" Google might provide the answer instead of just links to other sites.

The coming shift has major implications for Google, which dominates the Internet search market with around 66 percent market share and more than 75 percent of all search-ad revenue. The Mountain View, Calif., company has succeeded because of the strength and ease of its keyword-search technology, which in turn fueled Google's search ads, which appear next to search results. That business now generates the majority of Google's $37 billion in annual revenue.

Now Google is taking action to maintain that lead. The Internet giant is trying to stay ahead of Microsoft's Bing in web search, catch up to Apple's Siri voice-activated mobile search, and beat back rivals in niches such as product search.

Read more on Google's big plans at The Wall Street Journal.