The set of all points that share a property. This usually results in a curve or surface.
Example:
Circle:
- A Circle is "the locus of points on a plane that are a certain distance from a central point".
- A circle is the locus of points that are equidistant from a fixed point (the center).
Parabola:
- A parabola is the locus of points that are equidistant from a point (the focus) and a line (the directrix).
Ellipse:
- An ellipse is the locus of points whereby the sum of the distances from 2 fixed points (the foci) is constant.
- A hyperbola is the locus of points where the difference in the distance to two fixed foci is constant.