Stats are how well your character is in a certain area. Each one effects how well your character can Aim. They can be as little as 0 or as high as 100, and can be altered based on Game affects and based on Post Awards.
They go as follows:
Firearms: Skill with ranged weapons
Strength: Skill with melee weapons, as well as feats of strength
Intelligence: Characters with higher intelligence may receive help with solving puzzles.
Stamina: Resistance to physical status effects, and ability to undertake strenuous activity for a long period of time.
Charisma: Charm, character, presence, all these things combine to affect how easily the character can influence others and gain or lose bond.
Wits: Reaction speeds, affects how quickly you can move and react to danger
Moderation: Resistance to Mental Effects and how fearful they can be