What distinguishes a line from a plane?

The distinguishing characteristic between a line and a plane is that a line is one-dimensional, extending infinitely in both directions and can be defined by two points. In contrast, a plane is two-dimensional and extends infinitely in all directions within that two-dimensional space.

While a line consists of an infinite collection of points arranged in a straight path, a plane can be visualized as a flat surface. It includes length and breadth, but no fixed thickness. Because of this, a line can be conceptualized as narrower in scope, being a single dimension, whereas a plane encompasses a wider area and incorporates depth in a different sense—namely, it can contain multiple lines, points, and shapes within its surface.

Understanding this distinction clarifies the spatial properties of each geometric figure, outlining how they exist and relate to each other within mathematical contexts.