Rubik's Cube is a 3-D mechanical puzzle invented in 1974 by Hungarian sculptor and professor of architecture Ernő Rubik. Originally called the "Magic Cube", the puzzle was licensed by Rubik to be sold by Ideal Toy Corp. in 1980 and won the German Game of the Year special award for Best Puzzle that year. As of January 2009, 350 million cubes had been sold worldwide making it the world's top-selling puzzle game. It is widely considered to be the world's best-selling toy. There are more than 43 quintillion possible configurations, or 43,252,003,274,489,856,000 to be exact. Allowing a second for each turn, it would take 1,400 trillion years to go through all the possible configurations. After now thirty years of brainstorming, a famous open problem about the Cube has finally been resolved - 20 is the number. No matter how mixed up the Cube is, it can be solved in 20 moves or less.