From ‘Living with the Master. Reminiscences’ by Kunjuswami

Sri Bhagavan said there were three kinds of japa. Uccha japa, Upamsa japa and Manasika japa. Uccha japa is that which you do by moving your lips. Upamsa japa is japa that is done without movement of lips. The best is Manasika japa which is mental japa