Neutron stars are formed in supernovae from the collapse of a stellar core too
massive to become a white dwarf. Neutron stars are supported by the pressure of
Their maximum mass is probably between 2 and 3 solar masses.
Pulsars are magnetized rotating neutron stars that emit beams of radiation. Once or twice each rotation the beam crosses the Earth, and we can detect it. Pulsar periods range from milliseconds to tens of seconds. Listen to the sounds of pulsars here.
Stellar-mass black holes are the endpoint of evolution of the most massive stars. They may be formed in hypernova explosions, accompanied by gamma ray bursts.