I chord (Roman numeral I)

Definition

The I chord, also known as the tonic chord, is the primary chord in a key. It is built on the first scale degree and represents stability and resolution.

Analogy

Think of the I chord as the home base in a game of musical baseball. Just like how you always start and end at home base, the I chord is where a piece of music feels most resolved and stable.

Related terms

Dominant function: This term refers to chords or progressions that create tension and lead to resolution. They often include the V or vii° chords.

Predominant function: These are chords or progressions that prepare for the dominant function by creating a sense of tension without fully resolving it. Common examples include ii, IV, and vi chords.

Roman numeral notation: A system used to represent chords in relation to their position within a key using uppercase Roman numerals for major chords (I, IV) and lowercase for minor chords (ii, vi).