Plasma

In physics and chemistry, Plasma is a partially ionized gas in which a certain proportion of electrons are actually free of their atomic orbits rather than being bound to a single atom or molecule. The ability of the negative charges to move somewhat independently makes the plasma electrically conductive, making it respond strongly to electromagnetic fields. Plasma therefore has properties quite unlike those of solids, liquids, or gases and is considered to be a fourth, distinct state of matter. Plasma typically takes the form of neutral, gas-like clouds created by great sources of heat; for example, in the case of stars, or the nebulae from which stars form.

Weaponry
Plasma is a common ammunition type used in Directed Energy Weaponry. Heating the plasma to extremely high temperatures and surrounding it with a protective barrier (plasma cell, or heated plasma cylinder), a small generator within the weapon discharges a controlled bolt of (typically red) plasma toward it's target, causing the weapon's victim to suffer traumatic plasma burns that can prove fatal, if not intensely painful.

Plasma-based weapons are found everywhere, from a starship's cannons to the weapon in an soldier's hands in an army. Some people have even learned how to use magnetic fields to turn plasma into a melee weapon, like a sword or spear.

Vehicles
The engines of most vehicles in the galaxy, both atmospheric and exo-atmospheric, are usually plasma engines. Slow-burning as not to expend fuel, plasma engines are found in both large and small vehicles, and are renowned for their efficiency over the more powerful, yet faster-burning ion engines.

Shielding
Commonly known as "Energy Shields", plasma shields are found in high-tech armor and vehicles across the galaxy. Using magnetic fields to create a shield that repels most attacks, plasma shielding technology is widely known as an expensive, yet worthy, investment for anyone who gets shot at regularly.