Fox Illinois (April 11) -- More than two billion users have accepted Facebook's terms and conditions when joining—and most of those users probably didn't read through the fine print to know exactly what they were agreeing to. Facebook can track users’ location through GPS, Bluetooth and WIFI. It can collect payment information, like a credit card, when users make purchases through the site. It can even pick up on keywords users search or say in conversations. Karrie Karahalios, a University of Illinois Computer Science Professor, said the idea of online privacy is still a new concept.