One note does most of the emotional work in E minor, and it's C. Sitting just a half step above B, the fifth of the scale, C leans down toward it like a sigh. Take C out and E minor sounds plain and a little neutral. Put it back and the music turns wistful, serious, slightly heavy-hearted. That single note, the flat sixth, is why E minor sounds like the standard minor key so many listeners recognise as sad before they can say why.
A scale is a set of notes, and when you stack every other note of it you get chords. A triad is a three-note chord built that way: a root, the note two letters up, and the note two letters above that. A seventh chord adds one more stacked note on top. Do this on each note of E minor and you get seven chords:
The Roman numerals tell you which note of the scale each chord sits on. Lowercase means minor, uppercase means major, and the little circle means diminished, a tense, unstable chord. The "b" in front of III, VI and VII means those chords sit a little lower than they would in a major key.
Notice where C turns up: in F#dim, in Am and in the C major chord itself. Those three chords carry the scale's melancholy most strongly. Em is home, G and D feel bright and open, and Bm sits quietly in between.
Play Em, then C, on a piano or any instrument. The two chords share two notes, E and G. Only one note moves: B rises a half step to C. That tiny shift is enough to change the light in the room. Go back from C to Em and the C sinks back to B, which feels like coming home after a sad thought.
Here's something worth hearing for yourself: the v chord, Bm, is minor in this scale. In major keys the chord on the fifth note is major and pulls hard back to home. Here the pull is gentler and more resigned, which is part of why natural minor sounds reflective rather than urgent. Many songwriters get their sense of arrival from the bVII instead, letting D step up to Em.
A progression to try: Em - C - G - D, two beats or a bar each, looped. It's i - bVI - bIII - bVII, a shape you'll hear constantly in pop, rock and film music. It starts dark, sinks deeper on C, opens up on G, then D lifts you back to Em. For a moodier variation, try Em - Am - C - Bm, which keeps C in the air for longer.
The notes of E minor are E, F#, G, A, B, C, D. A whole step is two piano keys apart (skipping one); a half step is the very next key. The natural minor pattern is W - H - W - W - H - W - W. Starting on E:
Each letter appears exactly once, which is the rule for spelling a scale. That's why the second note is F# and not Gb: we need some kind of F, and the whole step from E lands on F#. In formula terms the notes are 1, 2, b3, 4, 5, b6, b7. G is the minor third that makes it minor, and C is that flat sixth.
With only one sharp, the key signature (the sharps or flats written at the start of each line of sheet music) is about as simple as it gets. It's the same signature as G major, because E minor uses exactly the same notes. G major is called its relative major: same notes, different home. Lean on E and it sounds sad; lean on G and it sounds cheerful.
You may see a mention of Fb Aeolian somewhere. It sounds identical but would need 11 flats to write. Nobody uses it in practice, so you can happily forget it exists. E minor is the friendly spelling.
E, G and B are the stable notes, the ones a tune can rest on. The others want to move. C is the most expressive: let it fall a half step to B and you'll hear that sighing quality straight away. Singers love holding a C over an Em chord for a moment of ache before resolving.
F# tends to step up to G or down to E. D usually slides back down to C or B rather than reaching up to E, since the whole step below home gives a softer landing than a major key's leading note. Try humming a phrase that climbs E-F#-G, touches C, then drifts down C-B-A-G-F#-E. That shape is pure E minor.
E minor sits beautifully on guitar because the open low E string is the root. You'll also find E at the 12th and 24th frets of the low E (6th) string, and at the 7th and 19th frets of the A (5th) string. Strum the open Em chord, let the low E ring, then pick out the scale starting from the 7th fret of the A string to hear how C lands above B in a different spot on the neck.
Loop Em and C for a full minute, on any instrument or a recording. Over the Em, sing or play only B. When the chord changes to C, nudge that B up to C. Then switch it round: hold C over Em and listen to it rub until you let it fall to B.
For the bigger picture, read The Natural Minor Scale (Aeolian Mode).