  It has now been just over four decades since the first discovery of a
millisecond spin period pulsar (MSP), B1937+21, by Don Backer and collaborators
in late 1982. This finding of an entirely new class of astronomical object
revolutionized pulsar astronomy and provided inspiration for novel scientific
investigation for decades to come, continuing to the current day and beyond.
Here we review the events leading to the discovery, based on archival material,
personal correspondence, and first-hand accounts of several of the
participants. We also briefly review the enormous impact that MSPs have had on
physics and astronomy by highlighting major MSP-related science of the past 40
years.
