Rubik's Cube Rubik's Cube Rubik's Cube is a 3-D combination 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 via businessman Tibor Laczi and Seven Towns founder Tom Kremer, and won the German Game of the Year special award for Best Puzzle that year. , 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. On the original classic Rubik's Cube, each of the
Two-cube calendar Two-cube calendar A two-cube calendar is a desk calendar consisting of two cubes with faces marked by digits 0 through 9. Each face of each cube is marked with a single digit, and it is possible to arrange the cubes so that any chosen day of the month (from 01, 02, ... through 31) is visible on the two front faces. A puzzle about the two-cube calendar was described in Gardner's column in "Scientific American". In the puzzle discussed in "Mathematical Circus" (1992), two visible faces of one cube have digits 1 and 2 on them, and three visible faces