A business system for organizing and managing product development, operational work, suppliers and customer relationships in which, compared to the former mass production system, it takes less human effort, less space, less capital, less material and less time to make products with fewer defects and exactly according to customer requirements. 

Lean production was introduced by Toyota after World War II. Since 1990, Lean production compared to mass production systems typically cost half the human effort, half the production space and capital investment for a given amount of capacity, and a fraction of the development time and lead time, while making a wider variety of products, in smaller quantities and with far fewer defects. (Womack, Jones and Roos 1990, pg. 13.)
The term was first used by John Krafcik, a research assistant at the Massachusetts Institute of Technology. He introduced it in the late 1980s for the International Motor Vehicle Program. 

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