Definition: The sharps or flats placed at the beginning of a staff to indicate the tonality (key) of the music.
The Savvy Take: The Key Signature is your “weather report.” It tells you the atmospheric conditions of the piece. Don’t just memorize the sharps; understand the mood. E Major (4 sharps) often feels bright and triumphant; Db Major (5 flats) often feels warm and lush.