What is Rubik's cube?
Rubik's cube is 50 years old this week. IT is a kind of three dimensional puzzle, invented in 1974 by the Hungarian architect and sculptor Professor Erno Rubik. He first called it the Magic Cube.
There are different models, but a typical cube has nine squares on each of its six faces. On each face there are squares in one of six colours: red, blue, green, white, yellow and orange. The squares xcan be moved and twisted to make them go in different directions, and the ultimate aim of the game is to move them so that in the end you have a solid square of one colour on each of the six sides.
Millions of people have struggled with the cube and given up - even to get one side complete is quite difficult - but once you have mastered it you can do it quickly, in fact people have races to see who can complete it fastest.