How music works on the page and in your ear. Notation and the staff (clefs, note values, meter and time signatures), the building blocks (whole and half steps, accidentals, enharmonics), major and minor scales and the key signatures (the circle of fifths, relative and parallel keys), intervals (number and quality, inversion), triads and seventh chords (qualities, inversions), diatonic harmony (Roman numerals, the function of tonic/subdominant/dominant, cadence types), voice-leading basics, rhythm reading, transposition, and the terms performers actually meet (dynamics, articulation, tempo) — plus the composition side: counterpoint and voice-leading rules (parallel fifths, resolving tendency tones), musical form (binary, ternary, rondo, sonata, 12-bar blues), Roman-numeral and figured-bass analysis, secondary dominants and modulation, the modes, and orchestration — instrument families, ranges, and transposing instruments (written vs concert pitch). Computed drills (interval math, key-signature counting, transposition) mix with concept questions; every explanation names the principle, the classic mix-up (interval quality vs number, relative vs parallel minor), and a rule you keep. For players, singers, producers, songwriters, and exam-takers alike.