## Annihilation

When corresponding particles of matter and antimatter (for example, an electron and a positron) contact each other, they annihilate each other, converting their masses into energy in the form of high-energy photons. The total energy produced can be calculated by using the equation $E = mc^2$.

## Antimatter

Every particle of matter in the Standard Model has a corresponding particle of antimatter. Anti-particles can be thought of as equal and opposite “reflections” of their matter counterparts. Matter and antimatter can annihilate with each other, producing large amounts of energy. Surprisingly, matter and antimatter are not exact reflections of each other; there are some slight asymmetries between them.