Open shape
x02220
A is the A major chord. Its notes are A, C♯ and E. A clear, stable sound. A natural home chord in a major key.
x02220
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Numbers show frets from the low E string to the high e string; x means don't play that string.
A is the I chord in A major, the IV chord in E major and the V chord in D major. That makes it a natural fit in songs written in those keys.
Every A, C♯ and E on the first 12 frets. The filled dots are the root, A. Build your own shape from any nearby group.
Other A chords
Other major chords