Eccentricity (mathematics)

Eccentricity in mathematics measures how "stretched out" or elongated a conic section (ellipse, parabola, or hyperbola) is. It is a number between 0 and 1 for ellipses, exactly 1 for parabolas, and greater than 1 for hyperbolas. For an ellipse, eccentricity indicates how much it deviates from being a perfect circle (which has eccentricity 0). A value closer to 0 means the shape is more circular, while a value closer to 1 indicates a more elongated form. This value helps classify and understand the geometric properties of these curves.