Please help improve this article by expanding it. Further information might be found on the talk page. (April 2008)

This article does not cite any references or sources. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (April 2008)

The function of identification is to map a known quantity to an unknown entity so as to make it known. The known quantity is called the identifier (or ID) and the unknown entity is what needs identification. A basic requirement for identification is that the ID be unique. IDs may be scoped, that is, they are unique only within a particular scope. IDs may also be built out of a collection of quantities such that they are unique on the collective.

Identification is the capability to find, retrieve, report, change, or delete specific data without ambiguity. This applies especially to information stored in databases. In database normalization, it is the central, defining function to the discipline.

[edit] Example

To retrieve the data stored about an individual with the Internal Revenue Service (IRS) of the United States, the IRS needs to be supplied with the individual's Social Security number (SSN). The SSN, then, "identifies" a unique individual to the IRS. No other living person has that SSN, and that individual is assumed to not have more than one SSN. Other data that the individual's SSN identifies with the IRS would be such things as his or her name, birthdate, and current employer.

[edit] See also

• Authentication
• Identification
• Profiling
• Profiling practices