Fundamental Concepts
1. The Tiny Dot · A mark of position with no size
A point is just a position, independent of where it sits on the plane.
A point marks a single position on the plane. We name it with a capital letter (P) and locate it with coordinates (x, y) — how far across (x) and how far up (y) from the origin O. Drag P — the coordinates change live; the dashed yellow lines show the projection onto each axis.
Stuck? Ask Guru
For subscribers · Selina ICSE: Fundamental Concepts
What this lesson covers
Try to break it
Try to measure its size. You can’t! A point is purely a position. It’s the tiny seed from which every line and shape in geometry grows.
How you build it
Mark a point on the canvas.
- Click the Point tool, then click anywhere on the canvas to drop a point.
The proof, step by step
Prove that the mark is a point — a position with no length, width, or thickness.
- A point represents a specific position or location.
- It has zero dimensions: no length, width, or thickness.
- It is denoted by a capital letter, such as A, P, or X.
Worked example
In geometry, a point is defined as a mark of position that has:
By definition, a geometric point has no dimensions. It occupies no space and has zero length, width, or thickness. It is purely a location.
- Length and width only
- Zero dimensions (no length, width, or thickness) — correct
- Thickness but no length
- Area and perimeter