SpaceX’s reusable cargo spacecraft used for International Space Station resupply is Dragon. The original Dragon capsule was developed under NASA’s Commercial Orbital Transportation Services program and later flew regular Commercial Resupply Services missions.
Dragon carries pressurized cargo inside its capsule and can return experiments, equipment, and other material to Earth. That return capability made it especially useful because many other cargo vehicles burn up during atmospheric reentry.
The first Dragon spacecraft launched in December 2010 and became the first commercial spacecraft to be recovered successfully from orbit. Dragon later supported dozens of cargo missions to the station.
Dragon is also the name family behind Crew Dragon, but the cargo and crew versions have different interiors, life-support systems, and mission roles. Northrop Grumman’s Cygnus and Russia’s Progress are separate resupply spacecraft.