The positron (antiparticle of the electron) is discovered by Carl D. Anderson.

The positron or antielectron is the particle with an electric charge of +1e, a spin of 1/2, and the same mass as an electron. It is the antiparticle of the electron. When a positron collides with an electron, annihilation occurs. If this collision occurs at low energies, it results in the production of two or more photons.

In particle physics, every type of particle of "ordinary" matter is associated with an antiparticle with the same mass but with opposite physical charges. For example, the antiparticle of the electron is the positron. While the electron has a negative electric charge, the positron has a positive electric charge, and is produced naturally in certain types of radioactive decay. The opposite is also true: the antiparticle of the positron is the electron.

The electron is a subatomic particle with a negative one elementary electric charge. It is a fundamental particle that comprises the ordinary matter that makes up the universe, along with up and down quarks.

Carl David Anderson was an American particle physicist who shared the 1936 Nobel Prize in Physics with Victor Hess for his discovery of the positron.