You have an albino, which, in the leopard gecko world, means that the gecko has no black pigment. There are 3 albino strains: Tremper, Bell and Las Vegas or Rainwater. They are not genetically compatible (i.e. a Tremper bred to a Bell will not produce albino offspring) and there's no way to really know which strain yours is though Tremper seems to be by far the most common. Your gecko also has markings that indicate the usual side-to-side bands at hatching were irregular which leads to a pattern called "stripe".