What is plasma?

It’s the 4th state of matter! What are the other states, you ask? Solid! Liquid! Gas! To get from solid to liquid, you add energy (heat it up!). To get from liquid to gas, you add energy (heat it up!). To get from gas to plasma, you add energy (heat it up!). But what cool things does plasma do that gas doesn’t? Have you ever seen a plasma? What are plasma good for?