How would you write the name of a segment different from naming a line?
A line is a one dimensional figure that extends infinetly in both directions.
Answer: A line is denoted with two arrowheads on the ends. A line segment is just denoted by a overbar with endpoints.
A line sengment is a straight line that has two end points. It has a fixed length.
Let's draw a diagram to undersrand better
Hence the lines and lines segments are denoted differently.