About 642 million people have lived in the United States since it became independent in 1776. A little over half of them, about 53 percent, are alive today.
How statisticians split a bill
A tiny model builds a world from symbols, reads its own map, and acts on a false one when you edit its mind. Runs in your browser.
For almost 30 years, the body of the climber became a macabre landmark for thousands attempting to reach the summit.