The document discusses different types of mail handled by a company's mail room, including incoming mail from outside sources, outgoing mail sent to customers and suppliers, and internal mail sent within the company. It provides guidance on processes for each type, such as opening, sorting, and dispatching mail. Equipment used in the mail room is also outlined, including folding machines, photocopiers, and franking machines. The document also describes the remittance book used to log cheque enclosures and signs of potentially dangerous mail items.