The Demo-1 mission of the SpaceX Crew Dragon is schedule for very, very early Saturday morning at 2:30 EST.
There won’t be anyone on board (at least that we know about). The mission is to deliver supplies to the ISS as well as simulated testing of the launch abort system.
When the vehicle returns to earth, SpaceX must demonstrate the ability to retrieve the capsule within one hour of landing.
If all goes well, there will be a test of the SuperDraco launch abort system in April. Demo-2, currently set for July, will be the first crewed mission to the ISS. This returns the United States to the ability to send crew to the ISS after the cancellation of the Space Shuttle program.