Line segment

In mathematics, a line segment is a part of a line that is bounded by two end points. See also interval (mathematics).

When the end points both lie on a circle, a line segment is called a chord. When they are both vertices of a polygon, it is an edge if they are adjacent vertices, and otherwise a diagonal.

The midpoint of a line segment is the 'middle' point: the unique point at an equal distance from the two end points.