Distance - The more distance in the ball the farther it will go.
Velocity - The speed a ball can reach in a shot.
Trajectory - The initial angle or curve that the ball takes at the beginning of its airborne travel in a shot.
Spin - The speed and direction at which the ball can be controlled upon landing and even while airborne.
Feel - The feeling you will sense when the club face comes in contact with the ball. Or the way the ball can land on the green. In most cases, softer is better. It all depends on the golfer's preference.
Durability - The stability or strength of the ball and the toughness it can handle.
Loft - The total peak from contact to the ball's landing.
Dimples - The pattern of markings on the cover of the ball. Used for aerodynamic purposes.
Cover - The outer layer or "shell" of the ball. Some balls also have an "inner cover" which is just one more layer to add to the ball's performance.
Core - The inner layer of the ball.
Carry - The distance the ball can travel through the air at roughly the same height.