ordering: indicates whether row order, column order, boustrophedon by row or boustrophedon by column ordering is being used.
originCorner: refers to the corner of the grid which is assumed to be the origin. (If a value of 'centre' is given, the grid must have odd numbers for each dimension.) For example, in a typical two dimensional case, the grid origin may have grid coordinates of (1,1) or (0,0), indicating first row, first position in the row.
cellPositionAtCorner: states whether or not the origin of a given cell is positioned at the corner with respect to its corresponding grid point. The corner referred to is that specified by originCorner. A value of 'false' for this attribute indicates that the origin of the given cell is at the centre with respect to its corresponding grid point.
originCoordinates: gives the coordinates of the local origin for the grid. Unless the grid in question is being located with respect to a larger grid, the values for the originCoordinates consist of all ones or all zeroes.