The procedure of export-import is as followed: First, the exporter (seller) and the importer (buyer) conclude a sales contract with a method of payment (usually a Letter of Credit: L/C).
The importer asks his bank to issue a letter of credit in favor of the beneficiary (the exporter/seller). Then, the importer's bank,which is called the issuing bank,asks a bank in the exporter's country,which is called the advising bank to advise or tell or confirm the exporter about the letter of credit.