White tigers are rare pigmentation variants of the Bengal tiger. Due to their ghost-like majesty, they are often a popular animal at zoos.
It is a common misconception that white tigers are albinos; unlike albinos, they still produce the pigment eumelanin. Just like people have different hair and eye color, white tigers are simply a variation. They represent what biologists call "natural phenotypical variation," an underlying genetic variation, among the Bengal tiger population.