<p>SAN FRANCISCO Facebook's greatest triumph has been to persuade a seventh of the world's population to share their personal lives online.</p><p>Now the social network is taking on its archrival, Google, with a search tool to mine that personal information, just as people are growing more cautious about sharing on the Internet and even occasionally removing what they have already put up.</p><p>Whether Facebook's more than one billion users will continue to divulge even more private details will determine whether so-called social search is the next step in how we navigate the online world. It will also determine whether Facebook has found a business model that will make it a lot of money.</p><p>"There's a big potential upside for both Facebook and users, but getting people to change their behaviors in relation to what they share will not be easy," said Andrew T. Stephen, who teaches marketing at the University of Pittsburgh and studies consumer behavior on online social networks.</p><p><a href="http://www.nytimes.com/2013/01/19/technology/with-graph-search-facebook-bets-on-more-sharing.html">Keep reading...</a></p><p>Read also:</p><p><a href="http://www.usatoday.com/story/tech/2013/01/18/facebook-graph-search-review/1844717/">First look: You might &#039;like&#039; Facebook&#039;s new search tool</a> (USA TODAY)</p><p><a href="http://news.cnet.com/8301-1023_3-57564801-93/facebook-graph-search-4-big-reasons-it-matters/">Facebook Graph Search: 4 big reasons it matters</a> (CNET)</p><p><a href="http://www.digitaltrends.com/social-media/how-facebook-could-monetize-facebook-graph-search/">Here&#039;s how Facebook could make money off of Graph Search</a> (Digital Trends)</p><p>Explore: <a href="http://news.google.com/news/more?ncl=d-aH9J7btk-whBMlMABxsO3qsD88M&ned=us">237 additional articles.</a></p>