Heterochromia of eyes is the different color of the iris of the right and left eyes or uneven color of different parts of the iris. It occurs because of lack or excess of melanin pigment. Heterochromia can be inherited or caused by some uninherited diseases.
With complete heterochromia one color different from the color of the iris another.
In partial heterochromia color of one part of the iris color is different from the rest.
Also there is the one more beautiful kind of heterochromia – central heterochromia, when the central zone of the iris has a different color than the peripheral zone, and the true iris color being the outer color. In this case both of eyes can be blue with dark rings for example.
Even some celebrities have heterochromatic eyes!