It represents the axes of a space. Suppose you have a 3d space. It has 3 axes (traditionally referred to as X, Y and Z), usually all pointing in orthogonal dire

It represents the axes of a space. Suppose you have a 3d space. It has 3 axes (traditionally referred to as X, Y and Z), usually all pointing in orthogonal directions, in some other space. The matrix holds the directions of these axes, one per column. Here's an example 3-d matrix: [ a d g ] [ b e h ] [ c f i ] (a,b,c) is the vector representing the direction of the X axis; (d,e,f), Y; (g,h,i), Z.