An air waybill is a receipt that is issued for goods by airlines and is evidence of the contract of carriage. An air waybill is not a title of ownership of goods. Air waybills are non-negotiable. The International Air Transport Association provides air waybill standards which most airlines follow.
The main functions of an air waybill are to act as a contract of carriage, as evidence of receipt of goods, as a freight bill, as a certificate of insurance and as a customs declaration (other documents are usually required by customs agents as well.) Air waybills contain an 11-digit number that can be used to book and track shipments. An air waybill will always contain the name and address of the carrying airline.