The present course introduces the fundamental concepts of plasma physics from the perspective of kinetic theory. The most important concept in plasmas is the collective effects. This course systematically overviews the various collective processes in plasmas which includes single-particle motion in plasmas, Landau damping, waves in plasmas, instabilities in plasmas, the effects of magnetic field, and various classifications of plasma instabilities. In particular, the plasma instabilities are categorized into several classes depending whether the plasma is immersed in magnetic field or not, whether there is gradient in plasmas, and based on the free energy source of instabilities.