Status: `DRAFT`

Prescriptive or descriptive: descriptive (this standard attempts to describe existing conventions)

This standard describes the basic moves for a 3x3x3 cube.

The move names in this standard originate from David Singmaster, around 1981 [1].

There are 18 basic moves:

Layer | ||||||

Clockwise | `U` | `L` | `F` | `R` | `B` | `D` |

Counter-Clockwise | `U'` | `L'` | `F'` | `R'` | `B'` | `D'` |

Double-Clockwise | `U2` | `L2` | `F2` | `R2` | `B2` | `D2` |

Each move corresponds to one unique way that an outer layer can be moved, while restoring the puzzle shape to a cube. Note that these moves keep each center in its original location (but possibly reoriented).

Note: This standard does *not* include double-counter-clockwise moves, since those can be written as double-clockwise moves for basic applications. This also matches the World Cube Association, which does not recognize double-counter-clockwise moves (e.g. for the Fewest Moves event) [2]. Extensions of this standard may include such moves.

There are 6 clockwise moves on a cube, corresponding to the 6 outer layers (standard 1.3.6): `U`

, `L`

, `F`

, `R`

, `B`

, `D`

.

Each face letter describes the following physical move:

- Look at the layer corresponding to that letter, from the outside of the cube.
- Turn the layer clockwise until the puzzle shape is restored.

Example: For a cube, `U`

describes turning the `U`

layer 90° clockwise. If we imagine the plane of the face as a clock face, this corresponds to moving the hour hand forward by 3 hours. Alternatively, this can be visualized as placing a screwdriver into the center of the layer, and turning it clockwise.

A counter-clockwise move is the inverse of a clockwise move. This is written as the corresponding layer letter with a `'`

symbol after it The `'`

symbol is pronounced “prime”.

There are 6 counter-clockwise moves: `U'`

, `L'`

, `F'`

, `R'`

, `B'`

, `D'`

.

Example: `U'`

is pronounced “U prime”.

A double clockwise move is the same as doing two clockwise moves consecutively. This is written as the corresponding layer letter with the number `2`

written after it.

There are 6 double-clockwise moves: `U2`

, `L2`

, `F2`

, `R2`

, `B2`

, `D2`

.

Note: In the 1980’s, it was common to write `2`

as a superscript `²`

. A lot of modern cubing software only understands the regular number suffix `2`

, so it is recommended to avoid the superscript version.

- Notes on Rubik’s Magic Cube, David Singmaster. Section 3. Notation.
- https://www.worldcubeassociation.org/regulations/guidelines.html#E2c4+

- Images/Diagrams/Visualizations
- “move” is a physical move, “turn” is only for metrics?