HALO info that everyone should know

Master Chief: Conscripted at age 6, he's a supersoldier with neural implants, reinforced bones and lightning-fast reflexes. His buffed-out Mjolnir armor augments these traits.
The Halo: ....a 10,000-kilometer-wide space ring bulit by an ancient race to house and study the Flood. It's also designed to wipe out all life in range to stop the Flood's spread.
The Covenant: An alliance of spacefaring races organized in religious castes. With their super weapons, they've vowed to wipe us from the galaxy. The "why" isn't clear yet.
Cortana: A one-of-a-kind artificial intelligence, she's based on Dr. Halsey, the genius behind most of Master Chief's technology. She spends mose of Halo plugged into his helmet.
The Flood: Parasitic organisms, they can infect almost any sentient creature and take over its body. These critters would consume all life in the galaxy if not kept in check by.......