The iris is the colored circle in the middle of the eye. The other visible part of your eye is the sclera, the protective coating generally known as the white of your eye. The sclera might not seem as interesting as the iris, but the cool part about it is that you can see blood vessels there.
iris recognition is great as a Biometric Template for authentication.
Vasculature (blood vessels) are also great for Biometric Template for authentication with the added benefit that you don’t need infrared light to see them.
Eyeprint ID should not be confused with Retinal recognition or with Facial recognition