Characters in Champions Online have eight (8) main stats from which a lot of secondary information is derived. These are similar, but no where near identical, to the Hero System stats used to play the Champions PnP game. The stats adn what they effect are:
STR (Strength) : Affects knockback distance, knockback resistance, what you can picking up and throw.
DEX (Dexterity) : Affects chance to crit, damage avoided when you dodge.
CON (Constitution) : Affects hit points, and hit point recovery.
INT (Intellect) : Reduces the cost of all powers, increases stealth detection, increases pet DPS.
EGO (Ego) : Affects crit severity, the strength of hold effects, and your ability to free yourself from some holds.
PRE (Presence) : Affects threat scaling more in Offensive role, less in Defensive role, and buff powers and pet HP.
REC (Recovery) : Affects your equilibrium, and the energy generated by your fighting attacks.
END (Endurance) : Affects your max energy, and the energy generated by your fighting attacks.
At the time of character creation you gain a background that increases your stats. If you choose one of the packages (selecting a Powerset instead of choosing ‘Custom Framework’) the background is already selected for you. The backgrounds appear to have no affect upon the game whatsoever except for setting your base starting stats bonuses. They are:
The Hard Target : +10 CON, END, STR, DEX & +4 INT, EGO, PRE, REC
The Untouchable : +10 END, DEX, EGO, REC & +4 CON, STR, INT, PRE
The Powerhouse : +10 CON, END, STR, REC & +4 DEX, INT, EGO, PRE
The Hero : +8 CON, STR, DEX, INT, EGO, PRE & +6 END, REC
The Heavy Hitter : +10 CON, END, STR, INT & +4 DEX, EGO, PRE, REC
The Stalwart : +10 CON, DEX, PRE, REC & +4 END, STR, INT, EGO
The Savant : +10 INT, EGO, PRE, REC & +4 CON, END, STR, DEX
The Preceptor : +10 DEX, INT, EGO, PRE & +4 CON, END, STR, REC
The Intimidator : +10 STR, INT, EGO, PRE & +4 CON, END, DEX, REC
As well, at levels 5 and then 13 you get to choose a ‘Super Stat’ for your character. These are stats that will increase as your character goes up in levels. It is best to choose stats that both fit the role of your character (a melee tank for example might choose STR and CON) but also stats that will get you good benefits from your powerset (the Force powerset has a Force Field that benefits from EGO and END).