Authentication is the act of confirming the truth of an attribute of a datum or entity. This might involve confirming the identity of a person, tracing the origins of an artifact, ensuring that a product is what its packaging and labeling claims to be, or assuring that a computer program is a trusted one.
In art

Art

Art is the product or process of deliberately arranging items in a way that influences and affects one or more of the senses, emotions, and intellect....

, antiques

Antiques

An antique is an old collectible item. It is collected or desirable because of its age , beauty, rarity, condition, utility, personal emotional connection, and/or other unique features...

, and anthropology

Anthropology

Anthropology is the study of humanity. It has origins in the humanities, the natural sciences, and the social sciences. The term "anthropology" is from the Greek anthrōpos , "man", understood to mean mankind or humanity, and -logia , "discourse" or "study", and was first used in 1501 by German...

, a common problem is verifying that a person has the said identity or a given artifact was produced by a certain person, or was produced in a certain place or period of history.

There are three types of techniques for doing this.

The first type authentication is accepting proof of identity given by a credible person which has evidence on the said identity or on the originator and the object under assessment as his artifact respectively.

The second type authentication is comparing the attributes of the object itself to what is known about objects of that origin.