Contents §1. Introduction Part I Magneto-fluid dynamical stability §2. Equations for the small disturbance §3. Boundary conditions §4. Effect of the magnetic field parallel to the wall §5. Effect of the uniform magnetic field parallel to the wall 5.1 Non-magnetic mode of the disturbance 5.2 Magneto-fluid dynamical disturbance at Rm ≪1 5.3 Magneto-fluid dynamical disturbance at Rm ≫1 §6. Important practical cases 6.1 Plane Poiseuille flow 6.2 Free boundary layer 6.3 Couette flow §7. Effect of the transverse magnetic field 7.1 Hartmann flow 7.2 Plane Couette flow Part II Magneto-fluid dynamical turbulence §8. Vortex motion in a uniform magnetic field §9. Weak turbulence in a uniform magnetic field §10. Homogeneous turbulence §11. Isotropic turbulence References