Asia is Earth's largest continent, covering about 30% of the world's land and home to more than half of all people alive today. It stretches from the Middle East in the west to Japan in the east, and from the frozen Arctic in the north to the tropical islands of Indonesia in the south.

Asia contains incredible variety. It includes the world's highest mountains (the Himalayas), vast deserts (like the Gobi), dense rainforests, and enormous cities like Tokyo, Delhi, and Shanghai. Some of the world's oldest civilizations developed here: China, India, Mesopotamia, and Persia all emerged in Asia thousands of years ago.

The continent includes more than 40 countries with many different cultures, languages, and climates. Russia (the world's largest country by area) spans both Asia and Europe. China and India each have populations of over a billion people. Tiny Singapore is smaller than many American cities but has become one of the world's most prosperous nations.

Major inventions originated in Asia: paper, gunpowder, the compass, printing, and the concept of zero all came from Asian civilizations. Today, Asia remains a center of innovation, manufacturing, and economic growth, producing everything from smartphones to automobiles to computer software.

When people say something is Asian, they're referring to this vast and diverse continent, though the word is so broad that it barely captures the enormous differences between, say, Saudi Arabia, Mongolia, and Thailand.