Draw minor and clockwise arcs

When you draw an arc, the specifications that you provide may define two, rather than one arc -- one minor (less than 180 degrees) and one major. The ARC command always draws the minor arc by default, in the counterclockwise direction.
For example, if you specify the Start, End, and Radius options, the center can be in two places, which can mean two possible arcs, one minor and one major, as you see here.

To draw the major arc, enter the radius as a negative number. Both arcs have a radius of 5, but the major arch was drawn by entering -5 as the radius.
When you specify an arc using the Angle option, again there are two possible arcs, one drawn counterclockwise and one drawn clockwise. The counterclockwise arc is the default. To draw the arc clockwise, use a negative number for the angle. Here you see two arcs. The one drawn counterclockwise was specified with an angle of 160 degrees, but the one drawn clockwise was specified with an angle of -200 degrees.