Line segment

What Is a Line Segment?

A line segment is a tiny piece of a straight line. It has two special points called endpoints. These endpoints are the farthest points on the segment. All the points between the endpoints are also part of the segment.

We can measure the distance between the two endpoints to find the length of the line segment. This distance is called the Euclidean distance.

Line segments are very useful in geometry. For example, the sides of shapes like triangles and squares are line segments. When the endpoints of a line segment are corners of a shape and are next to each other, the segment is called an edge. If the endpoints are not next to each other, the segment is called a diagonal.

Line segments can also connect points on curves. If both endpoints are on a curve, such as a circle, the line segment is called a chord.

Fun Facts About Line Segments

Line segments help us understand and describe many geometric shapes and their properties. They are used in many parts of geometry to solve problems and prove important ideas.