Double dribble
In basketball, an Illegal dribble (incorrectly identified in common wording as a double dribble) occurs when a player dribbles with two hands simultaneously.
Official NBA rules
In the National Basketball Association, a dribble is movement of the ball, caused by a player in control, who throws or touches the ball into the air or to the floor.
The dribble ends when the player:
Touches the ball simultaneously with both hands
Permits the ball to come to rest while he is in control of it
Touches the ball more than once while dribbling, before it touches the floor.
Penalty
Under NCAA and NFHS rules, if an illegal dribble violation occurs, then the ball is awarded to the opposing team out of bounds nearest the point where the violation took place. Under NBA rules, the ball is awarded to the opposing team at the nearest spot, but no closer to the endline than the free throw line extended.
See also
Carrying (basketball), dribbling by placing the hand palm up under the ball while dribbling