If Google delivers useless search results, just erase them and you won't see them again.

That's possible under a new system Google Inc. unveiled Thursday. Hoping to give its search engine a more personal touch, Google now lets users reshuffle results so their favorite Web sites get top billing and disliked destinations get discarded the next time they enter the same request.

It marks the first time that the Internet's most popular search engine has allowed its audience to alter the order of search results.

Although the revisions won't affect Google's closely guarded formulas for ranking Web sites, the Mountain View-based company isn't ruling out eventually tapping into collective wisdom of the crowds to tweak its Internet-searching algorithms.

For now, Google simply wants to make specific sets of results more useful to each individual that comes to its search engine, said Marissa Mayer, who oversees the company's search products. Users will have to have a personal login to take advantage of the editing feature.

"It should make the search results more dynamic," she said.

The decision to let people tinker with their results is a tacit acknowledgment that not even Google's seemingly omniscient search engine can possibly divine which Web sites will appeal to specific users. It also underscores how frequently people use Google to search for the same thing, such as "San Francisco hotels," over and over again.

Google's search recipe relies so heavily on automated ingredients that a variety of startup rivals such as Mahalo, Hakia and ChaCha have tried to carve out a new niche by relying on humans to vet and point to results.

But none of those have made a dent in a market that is increasingly controlled by Google, which processes more than 60 percent of the search requests made around the world.

Here's how the new system, called SearchWiki, works. If you're logged into Google when doing a search, you'll get results with a series of buttons below the links. Clicking on arrow pointing upward moves a result higher on the results page. That link will come back in that new spot the next time you search on the same term. Clicking on an "X" will delete the link so it doesn't appear the next time you make the same search.

Users will also be able to open a box to make notes about different sites so they can be read again in the future. The comments also will be shared with others who are logged in, if they click on a link for "See all notes for this SearchWiki."