C major

C major is the first scale most musicians learn — seven white keys on a piano, no sharps, no flats. It is the scale of lullabies, folk melodies, and countless classical themes from Mozart to Philip Glass. Because no accidentals interrupt its motion, C major feels transparent and neutral, which is exactly why it serves as the reference point for every other key. If you can hear the tonic-dominant pull between C and G, you can hear it anywhere.