Arrow wiki:

>For other uses, see Arrow (disambiguation). An arrow is a pointed projectile that is shot with a bow. It predates recorded history and is common to most cultures. An arrow consists of a long and thin shaft made formerly of wood and now also from aluminium or carbon fiber composite. It is pointed or armed with an arrowhead at one end and with a nock or notch in the other. Arrowheads fit hunting and military purpose better than a mere point, which is mostly useful for target-shooting. Near the notch end are vanes which keep the arrow pointed in the direction of travel. There are often three vanes but many fletchings have four or even more. They were originally made from feathers but are now often made of plastic.
See more at Wikipedia.org...

Circle wiki:

>This article is about the shape and mathematical concept of circle; for other meanings, see Circle (disambiguation). In Euclidean geometry, a circle is the set of all points at a fixed distance, called the radius, from a fixed point, called the centre (center). The points can only be those that are part of a conic section; within the set of a plane bisecting a cone. Circles are simple closed curves, dividing the plane into an interior and exterior. Sometimes the word circle is used to mean the interior, with the circle itself called the circumference. Usually however, the circumference means the length of the circle, and the interior of the circle is called a disk or disc.
See more at Wikipedia.org...