It is six sets of two strings each, really close together, almost so close that you can't pick each individual one. The top two strings, usually tuned to E and B, have two of the exact same string, same tuning, next to them. The other four strings, G, D, A, and E, have a string tuned to an octave above each corresponding note. This allows for some cool harmonics and octaves and an amazing, full, ringing sound when strummed.
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