This Animated Map...

The US Geological Survey (USGS) estimates that millions of earthquakes occur every year, but only one of them will be a "great earthquake" - that is, one with a magnitude of 8.0 or above. Here are where all the "great earthquakes" since 1900 have struck.

The US's railroad network is made up of around 140,000 miles of track, but many of our trains are slow and outdated. Over the last couple of decades, countries like China, Japan, the UK, and France have made large investments in high-speed rail, and some groups in the US are urging that we do the same. Here's what a high-speed rail network could look like in the US.

National Geographic reported in 2013 that sea levels would rise by 216 feet if all the land ice on the planet were to melt. This would dramatically reshape the continents and drown many of the world's major cities.

On July 16, 1945, the US conducted the world's first test of a nuclear weapon. Less than a month later, two bombs were dropped on the Japanese cities of Hiroshima and Nagasaki, bringing about the end of World War II. No nuclear bombs have been used as weapons since the attacks on Japan, but thousands of tests have been conducted - primarily by the US and USSR throughout the Cold War.

Hinduism, Buddhism, Christianity, Judaism, and Islam are five of the biggest religions in the world. Over the last few thousand years, these religious groups have shaped the course of history and had a profound influence on the trajectory of the human race.

Every time you visit a web page or send an email, data is being sent and received through an intricate cable system that stretches around the globe. Since the 1850s, we've been laying cables across oceans to become better connected. Today, there are hundreds of thousands of miles of fiber optic cables constantly transmitting data between nations.

The origin of Indo-European languages has long been a topic of debate among scholars and scientists. In 2012, a team of evolutionary biologists at the University of Auckland led by Dr. Quentin Atkinson released a study that found all modern IE languages could be traced back to a single root: Anatolian - the language of Anatolia, now modern-day Turkey.

In 1607, the English established their first permanent settlement in Jamestown, Virginia. Over the coming centuries, millions of people from around the globe were attracted to this New World that came to be the US for a chance at a better life. Today, more than 1 in 8 Americans are immigrants, and almost all are descendants of those born in foreign lands.