Plus the anti particles or anti quarks. Protons are made of 2 up quarks and 1 down quark. Neutrons are made of 2 down quarks and 1 up quark. All other baryons have 3 quarks and mesons have a quark and anti-quark pair. No one has been able to observe a single quark.
All particles decay either into a proton, electron or neutrino or a combination.
Even though this model explains all observed particles, it leaves a lot out. This is the micro world. On the macro scale, the universe has a lot of mass that is not composed of protons, electrons or neutrons. Another problem is that we do not know what gives mass to particles. These topics and other similar topics are being investigated in particle accelerators, where we can create temperatures that existed near the beginning of time, when all these particles were created.