It's the age of big data now. How big is big data? A set of data called "A Day on the Internet" tells us that in a single day, the entire content generated by the Internet could fill 168 million DVDs; 294 billion e-mails were sent out (equivalent to two years of U.S. paper mail); 2 million community posts were sent out (equivalent to 770 years' worth of text in Time magazine); 378,000 cell phones were sold, more than the number of births worldwide each day; and the amount of information on the Internet is more than the amount of information on the Internet in a single day. years' worth of text); 378,000 cell phones were sold, more than the 371,000 babies born every day worldwide ......