This Grid Size command of the Edit menu allows you to change the grid size. The grid size determines the number of unit squares in a department and the building. The grid size is equal to the length of one side of the unit square. The discrete area of a department is equal to its number of unit squares times the square of the grid size. Because of round off effects the discrete area of a department might not be exactly equal to its continuous area.
Click on OK to accept the modifications that you have made to the grid size. If you click on Cancel then all the modifications that you made to the grid size will be discarded and the grid size will not be modified.
For more information see: