It is the act of establishing or confirming something (or someone) as authentic, that is, that claims made by or about the thing are true.
This might involve confirming the identity of a person, the origins of an artifact, or assuring that a computer program is a trusted one.
In art, antiques, and anthropology, a common problem is verifying that a given artifact was produced by a certain famous person, or was produced in a certain place or period of history.
There are two types of techniques for doing this.
The first is comparing the attributes of the object itself to what is known about objects of that origin. For example, an art expert might look for similarities in the style of painting, check the location and form of a signature, or compare the object to an old photograph. A
n archaeologist might use carbon dating to verify the age of an artifact, do a chemical analysis of the materials used, or compare the style of construction or decoration to other artifacts of similar origin. The physics of sound and light, and comparison with a known physical environment, can be used to examine the authenticity of audio recordings, photographs, or videos.
Read the rest of the article here