Grady Stone, age 8, of High Point, N.C., for his question:

DO IDENTICAL TWINS HAVE IDENTICAL FINGERPRINTS?

No two fingerprints have as yet been found to be exactly alike. Identical twins have completely individual fingerprints.

Fingerprints are the impressions made by ridges on the end joints of the fingers and thumbs. These ridges form the fingerprint pattern, which remains unchanged throughout a person's entire life.

Fingerprints can be grouped according to the types of patterns and the number of ridges appearing between designated points within the patterns. There are three main groups: the arch, the loop and the whorl.

The FBI has nearly 200 million fingerprints on file in Washington.