A circle is is a geometric figure (shown here in bright pink) formed when a plane (red) intersects a cone (green) parallel to the base of the cone. A circle is a special case of an ellipse.
Illustration ID: MATHS-CONICS-circle-4
Illustration size: 25.0 Mpixels (71.5 MB uncompressed) - 5000x5000 pixels (16.7x16.7 in / 42.3x42.3 cm at 300 ppi)