Calls are generally transferred in either an attended or unattended fashion. Sometimes an attended transfer is called a "warm" or "consultative" transfer. It is typically performed for call types requiring high levels of service and/or emergency calls. In an attended transfer, the transferring agent remains on the line with the caller until a receiving agent is reached. The transferring agent may briefly introduce the customer and/or the nature of the call to the receiving agent before disconnecting from the line. An unattended transfer may also be called a "blind transfer," and may be used rather than an attended transfer to reduce costs. In an unattended transfer, the agent transfers the caller into a queue or voice mailbox and then drops the line. The transferring agent may provide the customer the name and/or telephone number of the person or department to which he or she is being transferred prior to the actual transfer.