<p><strong>Noun</strong></p><ul><li>A plane curve such that the sums of the distances of each point in its periphery from two fixed points, the foci, are equal.</li><li>It is a conic section formed by the intersection of a right circular cone by a plane that cuts the axis and the surface of the cone.</li><li>Typical equation: (x²/a²) + (y²/b²) = 1.</li><li>If a = b, the ellipse is a circle.</li></ul>