An attribute is a generic modifier that improves a character's performance in combat. There are four primary attributes that are shared across all professions and there is no separation between magical and physical distribution - two attributes improve offense, two attributes improve defense. Primary attributes are autoincreasing on each level. Its the same for all races and proffessions. There are 3 offense and 2 support attributes too. The player can increase an attribute point by investing points into trait lines and through gear. 
List of attributes
- Power — increases attack
- Precision — increases critical hit chance
- Toughness — increases armor
- Vitality — increases maximum health
- Prowess — Improves the damage multiplier on critical strikes.
- Malice — Improves the damage done by conditions like burning, poison, confusion, and bleeding.
- Expertise — Improves the duration of all conditions inflicted by the character.
- Concentration — Improves the duration of all boons applied by the character.
- Compassion — Improves all outgoing heals that your character does, including self heals.
- Brawn (warrior) — Improves the damage of warrior burst skills.
- Willpower (guardian) — Decreases the recharge on all virtues.
- Cunning (thief) — Decreases the recharge of the Steal ability.
- Empathy (ranger) — Improves pet attributes.
- Ingenuity (engineer) — Reduces the recharge on all tool-belt skills.
- Guile (mesmer) — Reduces the recharge on all Shatter skills.
- Intelligence (elementalist) — Reduces the recharge of the four elemental attunements.
- Hunger (necromancer) — Increases the size of the necromancer’s life-force pool.
Sources and distribution
Attribute points can be acquired from a number of different sources:
- Leveling — When a character levels up, they receive number of points to the 4 primary attributes (power,precision,toughness,vitality). The quantity of increases is larger at higher levels[verification requested].
- Items — Armor, upgrade components and weapons can provide additional attribute points. The set of attribute points is fixed for the item so the player must either select items which have attribute points they want or use a transmutation stone to take the statistics from another item.
- Traits — The player can choose traits which boost a particular attribute.
- Consumables — Increase attributes for a limited time.
- PAX East Preview: Izzy on Attributes and Iteration
- Play Your Way - Jon Peters on Traits and Attributes