4. Classes of passports and travel documents.- (1) The following classes of passports may be issued under this Act, namely: - (a) ordinary passport; (b) official passport; (c) diplomatic passport. (2) The following classes of travel documents may be issued under this Act, namely: - (a) emergency certificate authorising a person to enter India; (b) certificate of identity for the purpose of establishing the identity of person; (c) such other certificate or document as may be prescribed. (3) The Central Government shall, in consonance with the usage and practice followed by it in this behalf, prescribe the classes of persons to whom the classes of passports and travel documents referred to respectively in sub-section (1) and sub-section (2) may be issued under this Act. | 
