The present book discusses the heat transfer analysis on two-dimensional steady free or mixed convection flow of some non-Newtonian fluids over a stretching surface or cone surface or rotating disk surface. This book is divided into six chapters. The governing equations of the flow under consideration were solved with the appropriate boundary conditions by using well established numerical technique bvp4c method or Runge-Kutta-Fehlberg method of fourth fifth order or Spectral Quasi Linearization method. Chapter 1 intends to analyse the buoyancy effect on two-dimensional flow of Casson fluid and mixed convection over a nonlinear stretching sheet. The governing equations of the present study along with suitable boundary conditions are transformed into non dimensional differential equations along with appropriate boundary conditions by using similarity transformations. Spectral relaxation method is applied to study the considered problem as numerically. Moreover in case of linear stretching Exact solution is also performed. To improve the effectiveness and accuracy of the proposed method spectral over relaxation method is used.