Plasma (physics)

In physics and chemistry, a plasma is typically an ionized gas. Plasma is considered to be a distinct state of matter, in contrast to gases because of its unique properties. "Ionized" refers to presence of one or more free electrons which is not bound to an atom or molecule. The free electric charges make the plasma electrically conductive so that it responds strongly to electromagnetic fields.

Plasma typically takes the form of neutral gas-like clouds (e.g. stars) or charged ion beams, but may also include dust and grains (called dusty plasmas). They are typically formed by heating and ionizing a gas, stripping electrons away from atoms, thereby enabling the positive and negative charges to move more freely.