Plasma is by far the most common form of matter. Plasma in the stars and in the tenuous space between them makes up over 99% of the visible universe and perhaps most of that which is not visible. On earth we live upon an island of "ordinary" matter. The different states of matter generally found on earth are solid, liquid, and gas.
We have learned to work, play, and rest using these familiar states of matter. Sir William Crookes, an English physicist, identified a fourth state of matter, now called plasma, in 1879. Plasma temperature and densities range from relatively cool and tenuous (aurora borealis) to very hot and dense (the central core of a star). Ordinary solids, liquids, and gases are both electrically neutral and too cool or dense to be in a plasma state. The word "PLASMA" first applied to ionized gas by Dr. Irving Langmuir, an American chemist and physicist, in 1929.
Natural plasma examples include lightning, fire, and aurora borealis
Cold plasma examples are: fluorescent light, high-intensity arc lamp and some of street lights.