Tetromino
A tetromino, sometimes called tetramino or tetrimino, is a four-squared polyomino. The seven tetrominoes are I, O, T, S, Z, J, and L.
I
Other names include straight, stick, and long. This is the only tetromino that can make a "tetris" (four lines with one tetromino) outside of cascade games.
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O
Other names include square and block.
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T
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S
Other names include inverse skew.
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Z
Other names include skew.
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J
Other names include gamma or inverse L.
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L
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