7. Quarks

serve as the
foundation for matter. They are among the fundamental
components of protons and neutrons, which together
comprise the nucleus of an atom.

quarks

proposed that none of the hadrons, not even
the proton and neutron, are truly
fundamental, but instead are made up of
combinations of three more fundamental
point like entities called quarks.

Murray Gell-Mann and George Zweig

The heaviest particle according to the classification of particles.
These particles are subject to strong nuclear forces.

Hadron

Hadrons can be classified into 2 types

baryons and mesons

other examples of hadron's are

kaon, antiproton, antineutron