What is the SpaceX Demo-2 mission?

The Demo-2 mission is part of NASA’s Commercial Crew Program, and will fly two astronauts on SpaceX’s Crew Dragon spacecraft.

This mission is essentially a flight test to certify if SpaceX’s crew transportation system can be used to ferry crew to and from the space station regularly.

This is the final flight test for the system and intends to validate its different components, including the spacecraft (Crew Dragon), the launch vehicle (Falcon 9), the launch pad (LC-39A) and the operations capabilities.