MS Excel, what are the units of measure for cell height and width?

The title says it all. What are cell height and width measured in for MS Excel? I want to insert some images into a spreadsheet and I want to size the cells to fit the images. The default cell size is 8.43 X 12.75, but 8.43 X 12.75 what? Point? Inches? Anything?

Cells are measured in points. From Microsoft Office Assistance: