A "Bill of Lading" is actually somewhat more than a simple receipt for goods handed over by a "carrier" (such as a freight forwarding company) to a "shipper" (such as a Shipping Company).
See Bill of lading - Wikipedia, the free encyclopedia for a more definitive description of Bills of Lading.
If you are reading anything related to logistics you may also need to be aware of "Incoterms": see Incoterms - Wikipedia, the free encyclopedia
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PS In receiving the packages, the shipper doesn't unpack them to check their contents, but records that they have received a specific number of packages, with individual weights and dimensions listed, along with a declared list of contents, with no apparent damage to the packages and they have been loaded on the vessel for shipment.
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