The Shipper is the party responsible for arranging transportation. Legally, the Shipper, as indicated by the reference to that party in the bill of lading, is the person or organization who contracts with the Carrier for the transportation service.
The Seller of products is not by default the Shipper. The Incoterms© determine which party (Seller or Buyer) is responsible for arranging transportation. The EXW, FCA, FAS and FOB Incoterms© typically require for the Buyer to arrange transportation.
See also: Buyer, Carrier, Consignee, Discuss Contract Custom Solution