Duties and Taxes may apply on any international shipment whether your shipping to or from US & Canada. Many factors including the type of product, the country it was made in, the destination, etc. can affect the amount of duties and taxes. Some countries may also charge taxes on the cost of the shipping service itself.
These are assessed by the destination country. If you select the shipper to pay duties and taxes, these will be charged to your credit card as an adjustment. If you select the receiver to pay duties and taxes, these will be collected by the courier directly, usually before the delivery of the parcel can take place.