Identity document
An identity document is any document
Documentation is a term used in several different ways. Generally, documentation refers to the process of providing evidence.Modules of Documentation are Helpful...

 which may be used to verify aspects of a person's personal identity
Identity (philosophy)
In philosophy, identity, from , is the relation each thing bears just to itself. According to Leibniz's law two things sharing every attribute are not only similar, but are the same thing. The concept of sameness has given rise to the general concept of identity, as in personal identity and...

. If issued in the form of a small, mostly standard-sized card, it is usually called an identity card (IC). In some countries the possession of a government-produced identity card is compulsory while in others it may be voluntary. In countries which do not have formal identity documents, informal ones may in some circumstances be required.

In the absence of a formal identity document, some countries accept driving licences as the most effective method of proof of identity.