DIN is a unique Director identification number allotted by the Central Government to any person intending to be a Director or an existing director of a company. It is an 8-digit unique identification number which has a lifetime validity. Through DIN, details of the directors are maintained in a database. DIN is specific to a person, which means even if he is a director in 2 or more companies, he has to obtain only 1 DIN. And if he leaves a company and joins some other, the same DIN would work in the other company as well.