Mohammed Hamed Ahmed Soliman 
Toyota Production System Concepts [EPUB ebook] 
SMED – How to do a Quick Changeover?

The act of changing a line or machine from making one product to making another is called changeover. Changeover is when we switch from making one product (product A) to making a different product (product B). This involves getting the machines ready and getting everything prepared for the new process. It is considered a waste of time because you are not using the machine at that time, which means you are not producing anything. Additionally, you are still paying the operators and workers even though they are not being productive during that time. When automobile companies need to make new models, it can take them a little while or a long time to switch over their equipment.