All experimental tests so far are in agreement that quarks do not have internal structure.
Are there more?
Yes there are!
In big machines built by particle physicists, called particle accelerators, scientists have found evidence of the total of twelve elementary particles called quarks and leptons that are arranged in three families with similar characteristics.
On top of that, there are particles that carry interaction between particles (let them communicate with each other). They are called interaction or force carries: photon, gluon, Z0 boson and W± bosons.
There are 6 different quarks: up, down, charm, strange, top and bottom quark.
There are 6 leptons:
Electron, muon and tau carry electric charge
Electron neutrino, muon neutrino and tau neutrino are neutral
Finally, what about anti-particles?
For every elementary particle there is a corresponding anti-particle.
Each of the neutrinos has its corresponding anti-neutrino partner and they are called electron antineutrino, muon antineutrino and tau-antineutrino.
Have we come to an end?