# Rubik Puzzles

### Who is Erno Rubik?Edit

Erno Rubik is the inventor of the Rubik's cube and several other puzzles. The Rubik's cube is a permutation puzzle, just like many other puzzles in the Rubik brand.

### What is a permutation puzzle?Edit

A permutation puzzle is a type of puzzle in which parts are moved around the puzzle in a limited number of ways. Depending on the number of parts and the restrictions on movement, the puzzle has a number of possible configurations, or positions. The higher the number of possible positions, the more difficult it will be to solve the puzzle, in general.

One of the oldest and best-known permutation puzzles is the Towers of Hanoi, which consists of three sticks and seven tiles on one of the sticks, stacked in descending size. The second and third stick are left empty. It is the goal of the game to put all tiles on the third stick, moving one tile at a time, where a bigger tile can never be on top of a smaller tile. This takes 127 moves.

The Rubik's Cube has an astonishing number of 43 quintillion possible positions, one of which is the solved case.

## Types of Rubik PuzzleEdit

### CubesEdit

• 2x2x2 (mini/pocket/junior/ice)
• 3x3x3 (regular)
• 4x4x4 (revenge/master)
• 5x5x5 (professor)

## SpeedsolvingEdit

By speedsolving is meant solving a scrambled cube in the fastest possible time (bringing it back to its initial, solved position).

More on this topic can be found at the [speedcubing] website.

## TuningEdit

Tuning is the art of using tools and techniques to adjust the puzzle itself for the purpose of speedsolving. A puzzle can generally be tuned by

• lubricating (lubing), often with silicon spray(not oil-based)
• sanding