A square grid is a grid formed by tiling the plane regularly with squares.
See also
Buffon-Laplace Needle Problem, Checkerboard, Clean Tile Problem, Grid, Grid Graph, Hexagon, Square Tiling, Triangular Grid
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Cite this as:
Weisstein, Eric W. "Square Grid." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/SquareGrid.html