This appetite for personal data reflects a fundamental truth about Facebook and, by extension, the Internet economy as a whole: Facebook provides a free service that users pay for, in effect, by providing details about their lives, friendships, interests and activities. Facebook, in turn, uses that trove of information to attract advertisers, app makers and other business opportunities.
Up until a few years ago, such vast and easily accessible repositories of personal information were all but nonexistent. Their advent is driving a profound debate over the definition of privacy in an era when most people now carry information-transmitting devices with them all the time.
Capitalizing on personal data is a lucrative enterprise. Facebook is in the midst of planning for an initial public offering of its stock in May that could value the young company at more than $100 billion on the Nasdaq Stock Market.