A debt collector is a person or company that is responsible for recovering money owed by individuals or businesses. The term 'DUN' is an acronym for 'Demand for Payment', which is a formal notice sent to a debtor requesting payment of a debt. Debt collectors are often employed by creditors, such as banks, credit card companies, and other financial institutions, to recover unpaid debts. They may also be hired by private companies or individuals to collect on overdue accounts. Debt collectors typically use various methods to contact debtors, including phone calls, letters, emails, and even home visits.