What is the point?

Day 1

The overall point this time (I think) is that orthogonal and orthonormal are easy to mix up. I drew a little picture of Gon from Tekken because to orthoGONal vectors have a dot product of zero. I drew a bunch of Gons in neckties because an orthoNORMAL set of vectors is a bunch of normalized orthoGONal vectors.

I am studying principal components analysis first. The principal components are the left hand side of the singular value decomposition of X in X = $X = UDV^T$