Plasma is sometimes called the fourth state of matter, following the solid, liquid, and gas. Since the temperature of plasma is relatively high (over several thousand Kelvin), part or all of the particles in a gas state are ionized. Plasma therefore interacts with electric and magnetic fields quite easily, making plasma behave quite differently compared to the solid, liquid, and gas. In this course, we will learn one of the basic theories of plasma, called magnetohydrodynamics (MHD) which is focused on the macroscale behavior of plasma.