Rubik’s Cube, 1974
Rubik's initial attraction to inventing the Cube was not in producing the best selling toy puzzle in history. The structural design problem interested Rubik; he asked, "How could the blocks move independently without falling apart?" In Rubik's Cube, twenty-six individual little cubes or cubies make up the big Cube. Each layer of nine cubies can twist and the layers can overlap. Any three squares in a row, except diagonally, can join a new layer. Rubik's initial attempt to use elastic bands failed, his solution was to have the blocks hold themselves together by their shape. Rubik hand carved and assembled the little cubies together. He marked each side of the big Cube with adhesive paper of a different color, and started twisting.
"It was wonderful, to see how, after only a few turns, the colors became mixed, apparently in random fashion. It was tremendously satisfying to watch this color parade. Like after a nice walk when you have seen many lovely sights you decide to go home, after a while I decided it was time to go home, let us put the cubes back in order. And it was at that moment that I came face to face with the Big Challenge: What is the way home?" - Erno Rubik
