A more thorough explanation:

A debt collector is a business whose main purpose is to collect debts on behalf of third parties using the U.S. mails or an instrumentality of interstate commerce. This can include creditors who use a different name during the debt collection process to make it seem like a third party is collecting the debt.

However, under the Fair Debt Collections Practices Act (FDCPA), officers or employees of a creditor or those affiliated with the creditor by common ownership or corporate control are not considered debt collectors.

• A collection agency hired by a credit card company to collect overdue payments is a debt collector.
• A law firm hired by a landlord to collect unpaid rent is a debt collector.
• A bank that is trying to collect a debt using its own name is not considered a debt collector under the FDCPA.

The examples illustrate that a debt collector is a third-party business hired to collect debts on behalf of another party. The first two examples show businesses that fit the definition of a debt collector, while the third example shows a business that is not considered a debt collector under the FDCPA because it is the original creditor trying to collect the debt using its own name.