Open positions in chess refer to positions where there are not blocked pawns in the middle of the board. An open position may have pawns in the center if they are not blocked, or it may have no pawns in the center.
The definition is somewhat fluid. In theory it is possible to have an open center while having closed positions on the flanks, with interlocking pawn chains. But in practice, the layout of the center seems to set the tone for the overall position: a close center tends to be a closed position, and an open center leads to play for an open position overall.
Related Chess Tactics
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