We will introduce a new symmetry of electrodynamics and of quantum chromodynamics, called chiral spin symmetry, that is a symmetry of the electric part of the theory and that is larger than a symmetry of the theory as a whole. Observation of this symmetry in computer simulations of QCD in vacuum allows one to get insight into the origin of hadron spectra. Observation of the chiral spin symmetry at high temperatures suggests that what was formerly known as a quark-gluon plasma, and which was observed at BNL and CERN, is actually a matter that is populated of densely packed and strongly interacting hadron-like objects with approximate chiral spin symmetry