Fano plane

Definition
The Fano plane is a projective plane of order 2, so it has $$2^2 + 2 + 1 = 7$$ points. It is the unique projective plane of order 2, and can be constructed as the projective plane $$\mathbb{P}^2(\mathbb{F}_2)$$ over defining ingredient::field:F2.

See also classification of projective planes of order 2.