The Circle

This part of the circle is a diameter. The distance across a circle through its center is called a diameter. A diameter cuts the circle in half.

Part	Name	Description
	Diameter	The distance across a circle through its center is called a diameter. It cuts the circle in half.
	Radius	A radius of a circle is the distance from the center to any point on the circumference. More than one radius are called radii.
	Chord	A chord is a straight line that joins any two points on the circle. The diameter is a chord that passes through the center of the circle.
	Arc	An arc is any part of the circle's circumference.
	Center	The center of the circle is the point that is equally distant from any point on the circle's circumference.
	Central Angle	A central angle of a circle has the center of the circle as its vertex.