Complex sentence: Shipping is the physical process of transporting commodities and merchandise goods and cargo by sea, and is extended in American English to refer to transport by land or air (International English: "carriage").
Split into simpler sentences: Shipping is the physical process of transporting commodities and merchandise goods and cargo. The term Shipping originally referred to transport by sea, but is extended in American English to refer to transport by land or air (International English: "carriage").