A line has no endpoints and can be extended on both sides. It is a one-dimensional object with no thickness, width, or depth. The symbol of a line is ↔.

Types of lines are Parallel, Perpendicular, and Intersecting lines.

Explanation: Two lines that lie in the same plane and never intersect are called parallel lines.

Lines that cross or intersect at a single point are called intersecting lines.

Lines that intersect at a right angle (90°) are called perpendicular lines.

Explanation:

"P" is the origin of the ray, while "Q" is the point it passes through. The direction of travel is shown by an arrow above the points as \$\overrightarrow(PQ)\$.