Kanban got its origins from Taiichi Ohno, who was a Japanese engineer and businessman. He is widely considered the father of the Toyota Production System, which is the system that Kanban is based from. This is also known as Lean Manufacturing, especially in the United States. He developed the Kanban system to help improve efficiency within manufacturing environments.
First Kanban Signals
Kanban uses a system of visual communication tools and strategies to replenish stock and other things along the manufacturing process. The first visual stock replenishment system was that of an empty box. When someone saw that a box that should contain parts was empty, they would know that it was time to replenish the product.
In order to avoid downtime while waiting on replenishment, many facilities would begin keeping two or more boxes of parts at the machine location. While this would certainly help to eliminate the risk of running out of essential parts while things were being made, it was also quite wasteful since a significant amount of parts would need to be there simply sitting until the first container was used up.
Finding a Solution
Toyota began looking at how supermarkets operated their shelf-stocking strategies. They knew that supermarkets needed to keep their shelves full in order to have inventory available for customers, but not too full or the products would spoil before they were sold. Applying these concepts to the Toyota manufacturing systems is how the Kanban system was developed.
Implementing Kanban Cards
In order to get the advantages of a supermarket style supply in an auto manufacturing facility, Taiichi Ohno came up with the concept of using visual communication to signal the need for supply replenishment. When a particular machine was beginning to run low on a particular part, a Kanban card of a specific color would be used to let the supply team know.