+−

The +− symbol means that White has a decisive advantage. With correct play the position is considered winning, or at least so favorable that Black would need a major White error or exceptional resources to escape.

It is an evaluation, not an official result. The game may continue, White may lose the advantage, and the final result could still be 1-0, 0-1, or a draw. The sign also does not necessarily announce a forced checkmate.

In PGN, a decisive White advantage is NAG $18. Plain text often writes it as +-. On the traditional scale it is stronger than ± and ⩲. The opposite sign, −+, favors Black.

The slash changes the meaning

Do not confuse it with +/-. +− or +- has no slash and evaluates a position; +/- contains a slash and, in the FIDE glossary for unplayed games, records a White win by forfeit.