Matter can exist as a solid, liquid or gas. Matter has also been proven to exist in two extreme states as plasma and as a Bose-Einstein condensate.
A Bose-Einstein condensate was first created in 1995, although Satyendra Bose and Albert Einstein predicted it decades earlier. A Bose-Einstein condensate is an extremely cold, extremely low energy state of matter. It is on the other end of the spectrum from plasma. Plasma is an extremely hot, extremely excited state of matter, generally found in stars. States of matter can be thought of in terms of energy, or temperature, with Bose-Einstein condensates being the coldest and least energetic; solids the next coldest; then liquids; then gases; and finally plasmas with extremely high temperature and energy.