When it was released in 2005, Spotlight was simply a quick and convenient way to search the contents of your local hard drive — to locate a document, say, or a lost e-mail. It’s been quietly gathering power with each new iteration: doubling as a calculator or a dictionary and offering Boolean (and/or) searches.

But in OS X Yosemite, the new Mac operating system unveiled Monday, Spotlight comes front and center — literally. When you tap on the magnifying glass, a search window pops up in the middle of the screen. And when you type a few characters, it doesn’t just search your local computer, it searches the Internet as well, delivering maps, Wikipedia articles and Web results stripped of their ads. Repeat: Stripped of their ads.

Microsoft (MSFT) is delighted that Apple is using its Bing service to search the Web. “Last year Bing became the default web search for Siri, and will now also be the default web search provider in the redesigned Spotlight search feature for the next generation of iOS and OS X,” a Microsoft spokesperson told Ad Age. “We’re excited about extending the Bing platform to help iOS and Mac customers find what they need to get things done.”

Google (GOOG) will not be so happy. Advertising — especially U.S. search advertising — pays for nearly everything Google does, from building driverless cars to wiring whole cities with fiber optics. According to eMarketer estimates, Google took in 70.8% of the $19.92 billion spent on U.S. search advertising last year.

If Apple hopes to disrupt Google by giving the information away for free, it’s got its work cut out for it. As Ad Age poins out:

“Apple’s search tool shows only a few results per query, meaning a lot less real estate for results. That means Apple would have to prove that its small number of results are accurate enough to fulfill someone’s query. Good-enough search has never been enough to unseat or take share from Google.”

LINK: Did Apple’s ‘Spotlight’ Update Just Sideline Google Search Ads?