Charged particle

In physics, a charged particle is a particle with an electric charge. It may be an ion, such as a molecule or atom with a surplus or deficit of electrons relative to protons. It can also be an electron or a proton, or another elementary particle, which are all believed to have the same charge (except antimatter). Another charged particle may be an atomic nucleus devoid of electrons, such as an alpha particle. A plasma is a collection of charged particles, atomic nuclei and separated electrons, but can also be a gas containing a significant proportion of charged particles. Charged particles are labeled as either positive (+) or negative (-). Only the existence of two "types" of charges are known, and the designations themselves are arbitrarily named. Nothing is inherent to a positively charged particle that makes it "positive", and the same goes for negatively charged particles.