Questions

that is simply a letter that the debt collector sends you asking for payment. The first time they contact you, they have 5 days to notify you of your rights as a consumer. Those rights are, in a nutshell:

----you have the right to request the name and address of the original creditor.
----you have the right to dispute the whole debt, or any part of the debt. If you send them notice in writing within 30 days of receiving their letter, telling them that you dispute the debt, they are required to stop all collection effort and get validation from original creditor, and provide it to you.

If a debt collector calls you, and then doesnt send you that letter with that disclosure of rights on it within the five days, they have just violated the fdcpa, federal law.