This book discusses all of the different types of particles found or believed to exist in the whole of the known universe. Elementary particles are particles with no measurable internal structure; that is, they are not composed of other particles. They are the fundamental objects of quantum field theory. Many families and sub-families of elementary particles exist. Elementary particles are classified according to their spin. Fermions have half-integer spin while bosons have integer spin. All the particles of the Standard Model have been experimentally observed, including the Higgs boson. Order at https: //www.createspace.com/5789454