Is a Biometric device an input output or storage device?

Answer 1

Most biometric devices would be input devices although they may also utilize storage devices and output devices in their functioning.

A biometric device usually takes in biometric information about a person and compares it to information stored in a database - much like username/password methods of authentication compare the username and password to the stored information for a user. Fingerprint scanners, read the fingerprint, convert it to a data stream and then compare it to the stored data previously recorded for the individual, retinal scanners read information about the retinal patterns of a user, convert it to data and compare it to stored data, etc. Note that biometric devices must rely on a storage device, but usually the storage device is not part of the biometric device. Instances of OUTPUT associated with a biometric device might be a signal to open a door or trigger an alarm, but again, the output usually comes from another device that the biometric device is connected to.

Answer 2

It would be an input device, considering its taking your fingerprint (or whatever else) and processing it to figure out are you the person you claim to be.

Answer 3

Well, it is both an input and an output device because in order for it to give you something, the output, you must input something into the Biometric reader.