An identity card (or identification card) is a card that is used to prove a person’s identity. Today such cards are often printed on a small, credit-card sized plastic cards that also feature a photograph of the person. Some countries require national identity cards to be carried by their citizens while others do not make this compulsory. When the identification incorporates a person’s photograph it is typically referred to as a ‘photo ID’.
Some countries use a driver’s license instead of a formal identification document because it contains similar information. Other countries, however, do not use driver’s licenses in this way because they can be easily forged. Many countries use a passport as de facto identification document. These identity documents are used to connect a specific person to information about them that is collected by the state such as their full name, birth date, address, gender and so on and is usually assigned a unique national identification number.