Plasma is a very high energy state of matter that is usually only found at high temperatures. Stars are extremely hot, which easily allows the development of plasma. Earth is much cooler, which makes it difficult for plasma to form. Plasma can still be found in lightning bolts and fire.
The most common type of energy/mass in the Universe is in the form of dark energy, followed by dark matter. Only about 4% of the Universe is in the form of "normal" (baryonic) matter. If it is specifically to this matter you refer: the most common state of matter is plasma, found in stars.
plasma makes up 99% of the visible and observable matter in the universe. plasma is a state of matter like solids and liqiuds and gases. this one is the fourth. it is also found in plasma tvs, stars and extremely hot places.