Alpha-numeric grid

An alphanumeric grid (also known as atlas grid) is a simple coordinate system on a grid in which each cell is identified by a combination of a letter and a number.

An advantage over numeric coordinates, which use two numbers instead of a number and a letter to refer to a grid cell, is that there can be no confusion over which coordinate refers to which direction.

Algebraic chess notation uses an alphanumeric grid to refer to the squares of a chessboard.

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