The Japanese term meaning signboard used for scheduling cards in Toyota-style production is kanban.
Kanban is a visual, demand-driven control system associated with Toyota’s just-in-time production. A kanban card, container, or electronic signal authorizes an upstream process to make or move a specified quantity only after downstream consumption creates the need. This “pull” approach helps limit excess inventory and makes shortages or bottlenecks visible.
Toyota engineer Taiichi Ohno developed the system after studying supermarket replenishment in the late 1940s. The idea was that a factory process could act like a supermarket: downstream workers withdraw only what they need, while the preceding process replenishes the amount consumed. Toyota applied this logic in its main plant machine shop in 1953.
Kanban is often confused with heijunka, which means production smoothing, and andon, a visual alert system for signaling problems. Kanban cards may appear in a heijunka box, but the terms describe different parts of the production system. Modern factories increasingly use electronic kanban signals instead of paper cards.