What is an endpoint in math? An endpoint in math is a point that is located at the end of a line segment or ray.
Point A and point B are endpoints for the line segment AB
Point C is an endpoint for ray CD.
Notice that point D is not an endpoint since it is not located at the end of the ray. In fact, the side of the ray that extends indefinitely can never have an endpoint!
From the above figure, we can conclude that a segment has 2 endpoints and a ray has 1 endpoint.
A line does not have any endpoint since both sides of the line extend indefinitely.