Toyota Motor Corporation's Toyota Production System embraces four very significant components. Just-in-time (JIT) production is a management philosophy aimed at eliminating waste from every aspect of manufacturing and its related activities. The term JIT refers to the production of only what is needed, when it is needed, in just the amount needed. Total quality control is a concept of quality operation of the business with all people in all areas of the company's organisation involved to meet customer needs. Total productive maintenance, on the other hand, is a concept of productive maintenance aimed at achieving overall effectiveness of the production system through the involvement of all the people in the organisation. Finally, computer integrated manufacturing is a concept to integrate the company operations from design, production and distribution to after-sales service and support in the field, through the use of computers and modern information technologies. The effectiveness of TPS has been expressed through simple, unambiguous performance metrics capable of transcending cultural and economic boundaries.