Affine transformations and Pseudo affine transformations of the plane

This thesis consists of five chapters. First part is introductory part. Essential basic concepts are reminded in the second part. Affine transformations, main results on affine transformations, Fermat-Torricelli points and the relationship with affine transformations, fixed point affine transformations invariant straight lines of some affine transformation in R^n without fixed points are given in the third part. Pseudo-affine transformations, triangle-reflections and g-triangle-reflections are given in the fourth part. A new characterization of line-to-line maps in the upper plane is considered in the fifth part.