Rubik's Cube

Understanding and Solving the Rubik's Cube Without Algorithms

The movement of the cube parts is facilitated by the rotation of the layers. 

The default rotation of an outer layer follows the right-hand rule. To understand the right-hand rule, form a fist with your right hand and extend your thumb outward, as shown in Figure 3.10. 

Initially, it may appear confusing, but when holding the cube in your left hand, the default rotation of any outer layer is equivalent to turning off a faucet with your right hand by 90 degrees. This analogy can help with recording and reproducing the movements.

In accordance with the notation of the World Cube Association (WCA), the default rotation of any outer layer is simply represented by its corresponding letter. For example, the default rotation of the R layer is represented by R. When indicating a 90-degree rotation in the opposite direction, an apostrophe ('), pronounced as "prime," is placed after the letter that represents the layer. Thus, R' indicates a 90-degree rotation of the R layer in the opposite direction to the right-hand rule.

For 180-degree rotations, the number 2 is placed after the letter representing the layer. For instance, U2 denotes a 180-degree rotation of the U layer. In this case, the direction of rotation does not matter, as the final result is always the same.

Key Knowledge: A 180-degree rotation of a layer always produces the same result, regardless of the direction of rotation.

App source: animcubejs.cubing.net/animcubejs.html