In 2004 articles popped up citing how Wal-Mart responded to Hurricane Frances by analyzing their data to better understand spending habits ahead of a tropical storm. With 3,600 stores in the US (at the time) and roughly 100 million customers, Wal-Mart has access to vast troves of customer information. So much so that consumer advocacy groups have raised privacy concerns. To put this into perspective, consider the following:
By its own count, Wal-Mart has 460 terabytes of data stored on Teradata mainframes, made by NCR, at its Bentonville headquarters. To put that in perspective, the Internet has less than half as much data, according to experts.