For every type of fundamental force, there is a particle that "carries" that force.
Some particles are the constituents of matter (like neutrons), and other particles are the force-carrier particles (like photons).
The Standard Model says that most matter particles are composite particles, made up of more fundamental particles called quarks.
However, there is another class of matter particles called leptons, which are also fundamental. Originally the electron was the only particle of this sort, but we now know of neutrinos, muons, and other leptons.
Only 6 types of leptons and 6 types of quarks plus four types of force-carrier particles are needed to explain all the observed particles.
Antimatter
