In this installment: planes! What are they, why are we so particular about them, and what do you need to know about them to start spinning? Planes are a concept we borrow from geometry to describe how a poi rotates in relation to our bodies and how closely we adhere to that relationship. For added fun, each plane has two sides, called "plane facing" that you have to keep track of when you turn because every time your body changes the side of the plane its on, the poi will seem to have changed the direction it's rotating in. This is one of those concepts that's really difficult for people starting out to wrap their heads around, but it's so fundamental to poi spinning you'll find almost no poi moves that don't require some skill at maintaining a given plane.