A chord is a combination of three or more musical notes played simultaneously. It forms the basis of harmony in music, providing depth and richness to melodies. Chords are typically built on scales, such as the major and minor scales, and can evoke different emotions depending on their structure and progression. In Western music, chords are often represented by letters, such as C, G, or D. Each letter corresponds to a specific set of notes. For example, a C major chord consists of the notes C, E, and G. Understanding chords is essential for musicians, as they are fundamental to songwriting and composition.