Plasma is the fourth state of matter along with solid, liquid, and gas. When a gas is subjected to enough energy (in the form of thermal, light, or electrical energy), it is converted to a mixture composed of electrons, ions, free radicals, and meta-stables called plasma. Usually, electrical energy is used to produce plasma. In an electric field, when super-speedy electrons hit the gas atoms and molecules, their outermost electrons are pulled out and a mixture of free electrons, ions, etc. is produced