What is Plasma?
Plasma is the fourth state of matter. The three other states are; solid, liquid, and gas. Plasma is a gas that has been energized to the point that the electrons have broken free from their atoms turning atoms to ions. When met with a high heat source or electric field the ionized gas becomes plasma.
Gases can become plasma in several ways, but all include intruducing energy to the gas. A spark in a gas will create a plasma. A hot gas passing through a big spark will turn the gas stream into a plasma stream that can be useful in some industries. For example: Plasma torches are used in the welding industry to cut metals.
The biggest form of plasma you will see is actually the sun. The sun's enormous heat rips electrons off the hydrogen and helium molecules that make up the sun. Essentially, the sun, like most stars, is a great big ball of plasma.