Where the cube came from

A design professor, a puzzle by accident, and a very big number.

In 1974, in Budapest, a young professor named Ernő Rubik was teaching design and architecture. He wanted a way to show his students how objects can move in three dimensions. So he built a small cube out of smaller blocks, one that could twist in every direction without falling apart. Then he turned it a few times. And then a few more. Getting it back was much harder than he expected. It took him about a month to solve his own invention. He called it the Magic Cube. It went on sale in Hungarian toy shops in 1977, and in 1980 it launched around the world under a new name: the Rubik's Cube. It became one of the best-selling puzzles ever made. Here's why it's so hard. A cube like this can be mixed into more than forty-three quintillion different patterns. That's forty-three, followed by eighteen zeros. If you checked one pattern every second, it would take about a hundred times the age of the universe. And only one of those patterns is solved. So how does anyone solve it? Not by luck. In 1982, the first world championship was held in Budapest. The winner solved the cube in under twenty-three seconds. In 2010, researchers used computers to prove that any mixed-up cube can be solved in twenty moves or fewer. You won't need anything like that. You'll learn a method: a few steps, done in order, using a handful of short move sequences called algorithms. That's how everyone learns. And by the end of this course, you'll be doing it too.