Ares I was the crew launch component of the Constellation program.
Originally named the "Crew Launch Vehicle" or CLV, the Ares name was chosen from the Greek deity Ares.
Unlike the Space Shuttle, where both crew and cargo were launched simultaneously on the same rocket, the plans for Project Constellation outlined having two separate launch vehicles, the Ares I and the Ares V, for crew and cargo, respectively.
Having two separate launch vehicles allows for more specialized designs for the crew and heavy cargo launch rockets.

The Ares I rocket was specifically being designed to launch the Orion Multi-Purpose Crew Vehicle.
Orion was intended as a crew capsule, similar in design to the Apollo program capsule, to transport astronauts to the International Space Station, the Moon, and eventually Mars.
Ares I might have also delivered some (limited) resources to orbit, including supplies for the International Space Station or subsequent delivery to the planned lunar base.
Ares I was the crew launch component of the Constellation program. Originally named the "Crew Launch Vehicle" or CLV, the Ares name was chosen from the Greek deity Ares. Unlike the Space Shuttle, where both crew and cargo were launched simultaneously on the same rocket, the plans for Project Constellation outlined having two separate launch vehicles, the Ares I and the Ares V, for crew and cargo, respectively. Having two separate launch vehicles allows for more specialized designs for the crew and heavy cargo launch rockets.
The Ares I rocket was specifically being designed to launch the Orion Multi-Purpose Crew Vehicle. Orion was intended as a crew capsule, similar in design to the Apollo program capsule, to transport astronauts to the International Space Station, the Moon, and eventually Mars. Ares I might have also delivered some (limited) resources to orbit, including supplies for the International Space Station or subsequent delivery to the planned lunar base.
Ares I