The Incoterms, or International Commercial Terms is a set of rules that outline the responsibilities and risks to be placed on the seller and receiver during an international trade process.
The diagram below will help you understand the responsibility between the seller and the buyer throughout the entire shipping process, from customs clearance and shipping insurance to exporting of courier services. Bear in mind that incoterms also has specific mode of transport that it covers and also Incoterms such as DDU is being replaced by a new term in compliance to INCOTERMS 2010.