Circle being drawn by a compass

The circle is one of the most basic geometric shapes.  Can you imagine our world without circles?  We use circles every day, from simply circling something on a paper, to the circular wheel on our car.  Although the circle is very basic, its applications are endless.  In this unit, we are going to study the circle.  We are going to look at angles and arcs in circles, special line segments in circles, equations of circles and then circumference and area of circles.