Two entries on big data lead this week’s edition of DLTJ Thursday Threads. The first is at the grandest scale possible: a calculation of the amount of information in the world. Add up all the digital memory (in cell phones, computers, and other devices) and analog media (for instance, paper) and it goes to a very big number. The authors try to put it in perspective, which for me brought home how insignificant my line of work can be. (All of our information is still less than 1% of what is encoded in the human DNA?) The second “big data” entry describes an effort to make sense of huge amounts of data in the National Archives through the use of visualization tools. Rounding out this week is a warning to those who run public computers — be on the look-out for key loggers that can be used to steal information from users.