Rubik’s Cube

The Rubik’s Cube, invented by Erno Rubik, is a 3-D mechanical puzzle. In 1980 it was sold by Ideal Toys after winning the German Game of the Year special award. By January 2009 the puzzle had sold 350 million units making it the worlds top-selling puzzle game.

The classic cube has six sides covered by nine stickers among six solid colors. Each face turns independently on a pivot mechanism which mixes the colors. To solve the puzzle the user had to make all the sides a solid color. Larry Nichols was granted a patent for his 2x2x2 puzzle two years before Rubik invented his cube. Rubik invented his cube while searching for a 3D tool to teach his Interior Design Class. The first batches were released in 1977.

The standard cubes measures approximately 2 ¼ inches on each side and the puzzle consists of twenty-six unique miniature cubes. All six faces are affixed to a core mechanism. Each piece pivots on a screw held by the center piece. Many users “solved” the cube by taking it apart, which was easily done, then re-assembling it. The original cube has eight corners and twelve edges, which means there are 8 ways to arrange the corner cubes. Seven of the edges can be oriented independently and the orientation of the eight depends on the other seven.

Since there are so many sides, edges, etc, the puzzle is advertised as having only “billions” of positions. The original Rubik’s Cube had no orientation markings although some did say Rubik’s Cube on the center white square. A memorized sequence of moves that has a desired effect on the cube, called an algorithm, comes from mathematical use of the algorithm which provides well-defined instructions for performing a task. Many of the algorithms are designed to transform only a small part of the cube without messing up other parts that have been solved, so that they can be repeated over the whole cube until solved. Towards the end of solving the puzzle the user must employ these algorithms which have little to no side effects on the rest of the cube in order to finally solve the puzzle.