The elementary particles that build the universe have two types: bosons and fermions, where the fermions are classified as Dirac, Weyl, and Majorana fermions. In recent years, Weyl fermions are found in condensed matter systems, and Weyl semimetals as a kind of quasiparticle, and they manifest themselves as Weyl points from dispersion relations. In contrast to high-energy physics which requires the stringent Lorentz symmetry, there are two types of Weyl points in condensed matter systems: type-I Weyl points with symmetric cone-like band structures and type-II Weyl points with strongly tilted band structures.