DNA is unique, unless you're identical twins, in which case you have identical DNA.
DNA (or genetic) fingerprinting is way of comparing DNA samples to see if they come from same person or different people.
Used in forensics science. DNA from hair, skin flakes, blood, semen taken from crime scene compared with DNA sample taken from suspect.
Can also be used in patenity tests to check if a man is the father of a particular child.
Some people think all genetic fingerprints should be stored on national genetic database so DNA from crime scene can be checked against everyone's in the country to see whose it was making solving crimes easier.