The building blocks of reality.
The three undefined terms upon which all of Euclidean geometry is built.
Euclid defined a point as 'that which has no part'—a concept of pure location without size.
Lines have arrows (forever). Segments have endpoints (stop).
Plain English: Geometry is a game played on an imaginary board. A Point is a specific spot. A Line is a straight path that never ends. A Plane is a flat surface (like a wall) that goes on forever.
Real-world example: Game Design. A 'Vertex' is a point. An 'Edge' is a segment. A 'Face' is a plane.
Confusing Ray and Line. A Ray starts at a point and goes one way (like a laser). A Line goes forever in BOTH ways.