Linear transformation

https://www.youtube.com/watch?v=kYB8IZa5AuE&list=PLZHQObOWTQDPD3MizzM2xVFitgF8hE_ab

Linear transformation can be understood as "function" that moves the vector (point in a grid) to a different set of locations.

Linear means that the "transformed grid must be parallel and evenly spaced"

Recording changes in î and j will keep track of all the points in the grid