Projection (set theory)

Projection (set theory) is a way to look at things from a different angle. It's like walking around a picture and looking at it from different sides. When we project a set of points onto a line or a plane, we look at the points from a different perspective. For example, let's say we have a set of points that represent a circle in the x-y plane. When we project it onto the x-axis, we look at the same set of points from the side, instead of from top-down like before. The projection of the points onto the x-axis will give us a line.