United Launch Alliance (ULA) is a joint venture of Lockheed Martin Space Systems and Boeing Defense, Space & Security. ULA was formed in December 2006 by combining the teams at these companies which provide spacecraft launch services to the government of the United States. ULA launches from both coasts of the US. They launch their Atlas V vehicle from LC-41 in Cape Canaveral and LC-3E at Vandeberg. Their Delta IV launches from LC-37 at Cape Canaveral and LC-6 at Vandenberg.
The Atlas V N22 is a crew rated variant of the Atlas V 422 - it sports two solid motor strap on boosters with two liquid fueled stages. It will be primarly used to support NASA's Commercial Crew program by taking the CST-100 to orbit.
This is the first crewed test flight of Starliner spacecraft. It will carry NASA astronauts Christopher Ferguson, Michael Fincke and Nicole Mann to the International Space Station.