In a world increasingly dependent on electronically stored information, both consumers and businesses are seeking greater data security. The answer could lie in biometric identification, in which the unique characteristics of part of a person's body - their hands, for example, or the pattern of their irises - are used to verify the identity of that individual. Some Japanese banks have already begun installing biometric ID systems at their ATMs in an effort to combat cash-card fraud. But biometric ID has many other uses, including keeping track of who enters and leaves offices, protecting computers from tampering, and preventing unauthorized entry to apartment buildings. Manufacturers of these hi-tech security systems report that demand is booming.