Raja yoga focuses more on mental control than how good you look and move in yoga pants. Known as the Kingly yoga, it incorporates all the other schools & adds advanced mental practices. The Path of Raja yoga is one of study & mind control to unite you with your highest self.  Leading you to control yourself & your world. While it asks the most it gives the greatest return of all yoga; it leads to supreme enlightenment.  While there are different forms and ways to attain this, Raja is the highest form.