What tells a player to raise or lower a note?

The note itself. A player reads notes written on the music sheet. Each note signifies a specific tune, the Do-Re-Me-Fa-Sol-La-Ti-Do syllables. this tells the player to raise or lower notes. Beyond the notes themselves, a sharp sign (#) tells the player to raise the note a half-step, and a flat sign (b) indicates that the note should be lowered a half-step.