Protons and neutrons are two subatomic particles that make up an atom.
There are two main categories of subatomic particles: fermions and bosons. Fermions are the particles we think of as “material”: leptons like the electron, neutrino, and prime numbers, and quarks like the up quark and others of its sizeable family. Gauge bosons are the particles that mediate the four fundamental forces of nature: the strong and weak nuclear forces, electromagnetism, and gravity. This includes the familiar photon and its much lesser-seen cousins, the W and Z bosons, gluons, and (physicists hope) the graviton, the much-sought-after particle that mediates gravitational interactions.
Neutron microscopes can use neutrons to create images.
It is important to understand the difference between subatomic particles and fundamental particles. Fundamental means that the particle has no minor constituents; It’s fundamental. Not all subatomic particles are fundamental, although all known fundamental particles are subatomic, that is, smaller than atoms. For example, protons and neutrons, the subatomic particles that make up the atom, are non-fundamental composite particles made up of even smaller quarks and gluons. Exotic particles like the tau neutrino or muons are subatomic because they are smaller than atoms, but it is important to remember that they are not part of the atoms that make up the visible structures of our universe.
Subatomic particles are so numerous and varied that physicists have used the term “particle zoo” to describe them. In the lepton domain, there are 3 types of electrons: electron, muon and tau, 3 types of neutrino and their antiparticles, which form 12 leptons. There are four known gauge bosons: the photon, the W and Z bosons, and the gluon. Two additional bosons, which almost certainly exist but have yet to be observed, include the Higgs boson and the graviton. This brings the total number of fundamental particles to 18. Add the top, bottom, top, weird, and lovely quarks and their antiquarks, and you have 30 fundamental subatomic particles.
However, this not all. You may remember that a proton or neutron is made up of three quarks. This includes two up and down quarks, and one of the remaining quarks, glued together with gluons in the nucleus of the atom. However, this is not the only possible configuration of quarks, just the most stable. If he could somehow take fundamental particles at will and put them together in arbitrary configurations, he could create thousands of new subatomic particles.
In fact, hundreds of these subatomic particles have been observed in particle accelerator experiments. They include mesons, which have only two quarks, and hadrons, which have three protons and similar neutrons. There are also the so-called glue balls or gluonium, subatomic particles composed only of gluons, and the so-called tetraquark, a kind of subatomic particle that would be composed of four quarks. Are there pentaquarks and beyond? Perhaps so, but finding them would require an experimental apparatus far superior to our current best.