Particle physics
However, many particles do not simply break apart, such as electrons. Because it does not break apart, the electron is called a fundamental particle. If you were to smash two super-fast electrons against each other, they would not break, but instead, they might create more particles around them without breaking (this is another form of decay, known as a hadron jet). The Standard Model says that there are 17 types of fundamental particles, but there are 61, because most can be created out of antimatter, and some can have a color charge.