What other parts of human body are unique other than finger prints?

Voice

Ok, so it’s not quite a body part, but your voice is unlike any one else’s. Some vocal characteristics are easy to detect, such as frequency (high or low) and intensity (loud or soft). Other traits, however, such as tightness, resonance, or nasality are usually more difficult to pinpoint. An individual’s unique vocal tract is partly genetic and partly learned. The length of one’s neck and the width of the pharynx plays a part, but so do learned characteristics such as lip rounding and vowel pronunciation. Based on these combined traits, scientists have already created systems to automatically recognize a person’s voice if it is pre-recorded in a database.