In Indian scenario it is Additoinal Security demanded for the credit sanctioning while in USA banking it is cosnidered as Primary securtiy . In Indian scenario it can be attached when Primary security fails to recover the overdue loan amount and in USA it is used to attach when there is default of borrower. In Indian scenario it is used generally for corporate (basically SME) finances while in USA it is used for Retail financing like car, house, Mortgage loans etc.