In trigonometry, the gradian – also known as the gon (from Ancient Greek γωνία (gōnía) 'angle'), grad, or grade – is a unit of measurement of an angle...

used in several fields and many scientific calculators support them. Decigrades (1⁄4000) were used with French artillery sights in World War I. An angular...

circle of 400 grads. Dividing grads into tenths to give a circle of 4000 decigrades has also been used in armies. Most military forces have adopted the French...

were adopted by France although decigrades also remained in use throughout World War I. Other nations also used decigrades. The United States, which copied...