The circle is a flat surface or area limited or closed by a circumference. It is a two-dimensional figure and is formed by making a curve where it will always have the same distance to the center. Its area can be calculated using the following formula.
a straight line extending from the center of a circle or sphere to the circumference or surface: The radius of a circle is half the diameter. ... the length of such a line. any radial or radiating part.
