Natural circles are common, such as the full moon or a slice of round fruit. The circle is the basis for the wheel, which, with related inventions such as gears, makes much of modern machinery …

A circle is a 2-dimensional closed shape that has a curved side whose ends meet to form a round shape. Learn about circles with concepts, properties, and examples.

There are two main slices of a circle. The Quadrant is a special sector with a right angle. It has a quarter of the circle's area.

Test your understanding of Circles with these 12 questions. Explore, prove, and apply important properties of circles that have to do with things like arc length, radians, inscribed angles, and …

Circles make the world go ’round. Learn about the all-important shape, the circle, in our handy guide.

What Is a Circle? A circle is a round-shaped figure that has no corners or edges. In geometry, a circle can be defined as a closed shape, two-dimensional shape, curved shape. A few things …

Circle worksheets, videos, tutorials and formulas involving arcs, chords, area, angles, secants and more.