In tacky spy films, a commonly used security measure is for a computer to scan a persons fingerprint or iris – the part of the eye surrounding the pupil. The pattern of a fingerprint or iris is unique to each individual.
The scanning techniques are not science fiction. Every person arrested in the UK has their fingerprints taken by a scanner. A scanner can scan a fingerprint and match it to an individual in a couple of seconds, and the same is true for irises. In addition, face and voice recognition software is rapidly being developed. Any one of these methods may one day be used to unlock your phone, or used to identify you at bank cash machines instead of using PIN numbers, or to recognise you at your car or house or place of work door and allow you entry to your car, house or place of work.
Further into the future, security cameras may be able to scan your face as you walk down the street and identify you as a wanted criminal.
If you turn to a life of crime therefore, it may be wise to dip your fingers in acid to remove fingerprints, undergo an iris transplant so that your irises are completely featureless, and undergo a face transplant to look like Tony Blair, because, as we all know, a British citizen may be prosecuted for petty theft, but their ex Prime Ministers are not prosecuted for war crimes.