Question

How would you write the name of a segment differently than the name of a line? What symbols would you use?

Answer 1

Segments have a horizontal line over the letters representing the endpoints.
Lines have arrows on the end of the horizontal lines and the letters can be any two points on the line.

Answer 2

Sometimes the line will have a name, usually a single lowercase letter in italics or cursive. You would just use the letter with nothing above it in that case.