The current paper is a review of some transformation techniques of partial differential equations (PDEs) using similarity techniques which have the ability to reduce the number of independent variables to be a single variable resulting in a simpler ordinary differential equation (ODEs). These techniques have the benefit to obtain some completely new solutions. The paper introduces a summary and literature review for method of characteristic lines, Bäcklund transformations, Cole-Hopf Transformation, Lie infinitesimals, Non-classical symmetry method, Potential Symmetry, direct methods and characteristic function method.