The Rubik's Cube is a mechanical puzzle invented in 1974 by Hungarian sculptor and professor of architecture Ernő Rubik. Originally called the "Magic Cube" by its inventor, this puzzle was renamed "Rubik's Cube" by Ideal Toys in 1980 and won the German Game of the Year special award for Best Puzzle that year. It is said to be the world's best-selling toy, with over 300,000,000 Rubik's Cubes and imitations sold worldwide.

In a classic Rubik's Cube, each of the six faces is covered by 9 stickers, among six solid colours (traditionally being white, yellow, orange, red, blue, and green). A pivot mechanism enables each face to turn independently, thus mixing up the colours. For the puzzle to be solved, each face must be a solid colour.

The Cube celebrated its twenty-fifth anniversary in 2005, when a special edition was released, featuring a sticker in the centre of the reflective face (which replaced the white face) with a "Rubik's Cube 1980-2005" logo, and different packaging.

There exist four widely available variations: the 2×2×2 (Pocket Cube, also Mini Cube, Junior Cube, or Ice Cube), the standard 3×3×3 cube, the 4×4×4 (Rubik's Revenge, or Master Cube), and the 5×5×5 (Professor's Cube). Recently, larger sizes are also on the market (V-Cube 6 and V-Cube 7). All of these items belong to a broad category of puzzles commonly referred to as "twisty puzzles".

For readability, 3x3x3 is frequently abbreviated 3×3 (and similarly for the other sizes) when there is no ambiguity. Common misspellings include "Rubix cube", "Rubics cube", "Rubick's cube", and "Rubiks cube".