Finite geometry and the Gale transform

The Gale transform is an involution on sets of points in a projective space. It plays a crucial role in several different subjects, such as algebraic geometry, optimization, coding theory, etc. Sometimes, in the literature, the Gale transform is used implicitly, without mentioning it as such. In the present paper, we give a short account of the algebraic and geometrical implications that the Gale transform has when it is applied to sets of points in finite projective spaces.