If you take any non-barred chord, every fret that you move up the neck will result in the chord being raised by one-half step.
E and F are shown. Pretend that your index finger rests across all the strings just behind the first fret. You have barred E up one-half tone to F.
If you move all the fingers of the E chord one string toward the high E, E becomes transformed into Am.
Jay
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