Betza notation

Betza notation describes the movement powers of a piece type. It does not record one specific move from one square to another. It is especially useful for variants containing pieces that do not exist in orthodox chess.

Its basic vocabulary uses letters called atoms. W means one orthogonal step, which is one square horizontally or vertically. F means one diagonal step. N means the knight's leap. Familiar shortcuts also exist: R for a rook's sliding movement, B for a bishop, Q for a queen, and K for a king.

Atoms written together combine possibilities. RN describes a piece that can move as a rook or a knight. Lowercase modifiers restrict the movement: c means capture only, m means a non-capturing move only, and other letters select directions such as forward or backward. Directions are read from the piece's perspective.

Extended Betza notation adds tools for multi-stage moves, conditional hopping, and effects on other squares. Software may implement different subsets, so complex descriptions should be exchanged with a known dialect in mind.