Cube notation is a compact language for describing turns. Once you can read it, every tutorial, algorithm sheet and app instruction becomes immediately usable.
The six face letters
- R — the right face
- L — the left face
- U — the up face
- D — the down face
- F — the front face
- B — the back face
Direction modifiers
A plain letter means a quarter turn clockwise, looking directly at that face. An apostrophe (R') means the same turn counter-clockwise. A 2 (R2) means a half turn — direction does not matter.
Reading a sequence
R U R' U' is four separate quarter turns performed in order. Keep the cube in the same orientation for the whole sequence, otherwise the letters no longer refer to the faces you think they do.
Why it matters in an app
When a solver shows you a move list, it is using this notation. Understanding it means you can follow along, check your work, and eventually stop needing the visual prompt at all.
