The Grid Properties dialog box lets you display or hide the chart grid. The grid consists of equally-spaced parallel and perpendicular lines that measure the height, size, or placement of the data markers. Major gridlines show the larger divisions on the axes. Minor gridlines show the smaller divisions between major gridlines.
Display Vertical: Major Grids
Enable to display vertical major gridlines.
Display Vertical: Minor Grids
Enable to display vertical minor gridlines.
Horizontal Grids: Major Grids
Enable to display horizontal major gridlines.