In some respect, we all have a hand in writing human history. Now that act is more literal than ever before if you are among the millions who tweet. In mid-April, the Library of Congress announced that it would be digitally archiving every tweet ever posted by any little blogging bird. The 210-year old institution adds this ever-growing record to its mammoth collection of every book, print, photo, map, or musical piece registered with the U.S. Copyright Office.