Eccentricity (mathematics)

In mathematics, eccentricity is a measure of how much a conic section deviates from being circular. It is primarily used in the context of conic sections, which include circles, ellipses, parabolas, and hyperbolas. Each type of conic section has a specific eccentricity value: 1. **Circle**: The eccentricity is 0. A circle can be thought of as a special case of an ellipse where the two foci coincide at the center.