Take a look at the numbers behind drones -- America's mysterious instruments in the war on terror.
On the eve of a speech by President Barack Obama about his administration's counterterrorism policy, Attorney General Eric Holder acknowledged for the first time Wednesday that U.S. drone strikes have killed four Americans overseas since 2009. Here's a look at drones by the numbers:
Have you ever wondered where the tradition of putting up a tree for Christmas came from? Or why we light a menorah for Hanukkah? Find out about the interesting origins of many holiday traditions right here.