SpaceX Dragon 1 in the context of SpaceX Crew Dragon

Dragon 2 is a class of partially reusable spacecraft developed, manufactured, and operated by the American space company SpaceX for flights to the International Space Station (ISS) and private spaceflight missions. The spacecraft, which consists of a reusable space capsule and an expendable trunk module, has two variants: the 4-person Crew Dragon and Cargo Dragon, a replacement for the Dragon 1 cargo capsule. The spacecraft launches atop a Falcon 9 Block 5 rocket, and the capsule returns to Earth through splashdown.

Crew Dragon's primary role is to transport crews to and from the ISS under NASA's Commercial Crew Program, a task handled by the Space Shuttle until it was retired in 2011. It will be joined by Boeing's Starliner in this role when NASA certifies it. Crew Dragon is also used for commercial flights to ISS and other destinations and is expected to be used to transport people to and from Axiom Space's planned space station.

Commercial Resupply Services (CRS) are a series of flights awarded by NASA for the delivery of cargo and supplies to the International Space Station (ISS) on commercially operated spacecraft.

The first phase of CRS contracts (CRS-1) were signed in 2008 and awarded $1.6 billion to SpaceX for twelve Dragon 1 and $1.9 billion to Orbital Sciences for eight Cygnus flights, covering deliveries to 2016. The first operational resupply missions were flown by SpaceX in 2012 (CRS SpX-1) and Orbital in 2014 (CRS Orb-1). In 2015, NASA extended CRS-1 to twenty flights for SpaceX and twelve flights for Orbital ATK.