Skip to content

Understanding Chords

A chord is three or more notes played at the same time. Chords are the harmonic foundation of nearly every song you will ever play. This handout explains what chords are, how they are built from scales, why some sound happy (major) and others sound sad (minor), and how this all connects to the chord shapes your fingers are learning on the fretboard.

When you strum your guitar with fingers pressing specific frets, several strings ring out together. That combination of notes sounding simultaneously is a chord. The specific notes you choose determine the chord’s name and its mood.

The simplest chords use three different notes and are called triads (from “tri” meaning three). Even though you might strum five or six strings for a guitar chord, only three distinct note names are involved — some notes are simply repeated at different octaves.

Before understanding how chords are built, you need one concept: the interval, which is the distance between two notes.

The distances are measured in half steps (one fret on the guitar) and whole steps (two frets):

Interval NameDistanceExample from C
Minor 2nd1 half step (1 fret)C to C#/Db
Major 2nd2 half steps (2 frets)C to D
Minor 3rd3 half steps (3 frets)C to Eb
Major 3rd4 half steps (4 frets)C to E
Perfect 5th7 half steps (7 frets)C to G

The two intervals that matter most for building basic chords are the major 3rd (4 half steps) and the minor 3rd (3 half steps).

A major chord is built from three notes called the root, the 3rd, and the 5th. Starting from the root note:

  1. Root — the starting note (the chord is named after this note)
  2. Major 3rd — 4 half steps above the root
  3. Perfect 5th — 7 half steps above the root

Example — C major chord:

  • Root: C
  • Major 3rd: E (C → C# → D → D# → E = 4 half steps)
  • Perfect 5th: G (C → C# → D → D# → E → F → F# → G = 7 half steps)

The notes in C major are: C - E - G

On your guitar, the open C chord shape places these three notes across five strings:

C
XOO
1
2
3
EADGBe

Notes: E(e string) - C(B string) - G(G string) - E(D string) - C(A string). Only three note names appear: C, E, and G — the triad. Some are repeated at different octaves.

A minor chord has a minor 3rd instead of a major 3rd. That single note is one half step (one fret) lower:

  1. Root — same
  2. Minor 3rd — 3 half steps above the root (instead of 4)
  3. Perfect 5th — 7 half steps above the root (same as major)

Example — Am chord (A minor):

  • Root: A
  • Minor 3rd: C (A → A# → B → C = 3 half steps)
  • Perfect 5th: E (A → A# → B → C → C# → D → D# → E = 7 half steps)

The notes in Am are: A - C - E

On your guitar (first learned in Session 3):

Am
XOO
1
2
3
EADGBe

Notes: E(e string) - C(B string) - A(G string) - E(D string) - A(A string). Three note names: A, C, E.

Major vs Minor — The One-Fret Difference

Section titled “Major vs Minor — The One-Fret Difference”

The entire difference between a major chord and a minor chord is one note — the 3rd — shifted by one fret:

  • Major 3rd = 4 half steps = happy, bright sound
  • Minor 3rd = 3 half steps = sad, dark sound

Listen to the difference: play E major (Session 5), then play Em (Session 2). The only note that changes is the G#/Ab (major 3rd) becoming G (minor 3rd) — one fret lower on string 3.

E
OOO
1
2
3
EADGBe
Em
OOOO
2
3
EADGBe

E major has G# on the G string (fret 1 = major 3rd). Em has G on the G string (open = minor 3rd). One finger lifted. One fret difference. The entire mood changes.

A power chord (introduced in Session 9) uses only two notes: the root and the 5th. It skips the 3rd entirely. Without a 3rd, the chord is neither major nor minor — it is neutral and strong. This is why power chords work so well in rock and metal: they are raw and aggressive, without the sweetness of major or the sadness of minor.

E5 power chord:

E5
OXXXX
1
EADGBe

Notes: E(6th string, root) - B(5th string fret 2, 5th). Only two note names: E and B.

Now you can decode any basic chord name:

Chord NameRootTypeExample Notes
CCMajor (default — no modifier)C - E - G
AmAMinor (lowercase “m”)A - C - E
EmEMinorE - G - B
DDMajorD - F# - A
GGMajorG - B - D
E5EPower chord (“5” = root + 5th only)E - B

When you see just a letter (like “G” or “D”), it means major. When you see a letter followed by “m” (like “Am” or “Em”), it means minor.

Exercise 1: Hear the Major vs Minor Difference

Section titled “Exercise 1: Hear the Major vs Minor Difference”

Play these chord pairs back to back, strumming each chord four times. Listen to the mood change:

Pair 1: E major → Em

E
OOO
1
2
3
EADGBe
Em
OOOO
2
3
EADGBe

Strum E major four times, then lift your finger from string 3 and strum Em four times. Major sounds bright; minor sounds dark.

Pair 2: A major → Am

A
XOO
1
2
3
EADGBe
Am
XOO
1
2
3
EADGBe

A major (introduced in Session 8) vs Am (from Session 3). Again, one note shifts by one fret and the whole feel changes.

Play the Em chord. While holding the shape, pluck each string individually and name the note:

Em
OOOO
2
3
EADGBe

Notes per string: E(e) - B(B) - G(G) - E(D) - B(A) - E(E). The three note names are E, G, B — the E minor triad. You are playing those three notes across all six strings.

Exercise 3: Power Chord — Hear the Neutrality

Section titled “Exercise 3: Power Chord — Hear the Neutrality”

Play the E5 power chord (from Session 9):

  • Finger 1 on fret 2, string 5
  • String 6 open
  • Only strum strings 6 and 5 (mute the rest)
E5
OXXXX
1
EADGBe

Now compare: play E major, then Em, then E5. Major is bright, minor is dark, power chord is neither — just raw power. This is the backbone of every rock riff in the course.

1. How many different note names make up a basic triad chord?

2. What is the difference between a major chord and a minor chord?

3. In a chord name, what does a lowercase “m” mean (as in “Am”)?

4. A power chord like E5 uses which two components of a chord?

5. The notes in a G major chord are G, B, and D. What interval is from G to B?

  1. Three different note names (the root, 3rd, and 5th).
  2. The 3rd is different: a major chord has a major 3rd (4 half steps above root), a minor chord has a minor 3rd (3 half steps above root). Everything else is the same.
  3. It means “minor” — the chord has a minor 3rd, giving it a darker, sadder sound.
  4. The root and the 5th only. No 3rd, which is why it sounds neither major nor minor.
  5. A major 3rd (4 half steps: G → G# → A → A# → B).

Every chord is built from a root, a 3rd, and a 5th. The 3rd determines the chord’s mood: major 3rd for bright/happy, minor 3rd for dark/sad, and no 3rd at all for the neutral power of a power chord. When you form a chord shape on the fretboard, you are arranging these three notes across your strings. Now when you see “Am” on a song sheet, you know it means A-C-E — and your fingers know where to put them.