History 101

E1. Fast Food

Cheap, quick and tasty, fast food became a culinary craze in the 1950s. But has our quest for convenience created an irreversible health crisis?

★ 6.8

E2. The Space Race

Fifteen international agencies spend $62 billion every year on space travel. What's fueling our costly — and dangerous — drive to explore the universe?

★ 7.2

E3. The Rise of China

In the 21st century, China has become a global economic powerhouse. Why was the rest of the world so slow to notice its rise to the top?

★ 7.8

E4. Plastics

Plastics have transformed how we live, but progress comes at a high price: 7.8 billion tons of waste. Are plastics a miracle or a catastrophe?

★ 7.5

E5. Oil and the Middle East

Oil has brought great wealth to the Middle East and ignited major wars. Is it a blessing or a curse for the region, as well as the rest of the world?

★ 7.7

E6. Robots

We share the planet with an estimated 9 million robots, from self-driving cars to surgical arms. Could they one day completely replace humans?

★ 7.0