If you are the sender of the package :
You'll find your tracking number on the proof of deposit (under the barcode) given to you at the post office counter on the day of shipment.
If you are the recipient of the parcel: (e.g. for an order placed on a website)
The tracking number is normally communicated to you by the website when your order is validated.
This is a combination of 13 alphanumeric characters (for example: 8D00432154798, 6Q00028724095, CK00879241952).
This number enables you to track your parcel and be informed of the various stages of its delivery.