A waybill number is a unique tracking number assigned to a package or parcel that allows it to be tracked in real-time. It is also known as a tracking number. The waybill is usually attached to the exterior of the package and contains all the information that the relevant authorities need to know about its point of origin, its contents, where it is headed, and the route it will take. The waybill is important for identifying and tracking the package, and it is used for information purposes. It is a non-negotiable document that acknowledges receipt of cargo and serves as evidence of the contract of carriage. Waybill numbers consist of letters and numbers, typically between 8 and 40 characters long, sometimes with spaces or hyphens between groupings of characters. The waybill number is usually printed on the shipping label as a barcode that can be scanned by anyone with a barcode reader or smartphone.