(a) Weyl points are twofold degenerate band crossings of two singly degenerate bands. (b) Dirac points are fourfold degenerate band crossings of two twofold degenerate bands. (c) Triple-points are threefold degenerate band crossings of a singly and a doubly degenerate band. Here a pair is shown. (d) A spin-1 generalization of a Weyl fermion.^[17]