Kanban is a methodology that originated from the Toyota Production System as a way to improve efficiency in manufacturing processes. It uses visual signals (known as Kanban cards) to trigger the movement of work through a process. The main principles of Kanban include limiting work in progress (WIP), visualizing the work process, and managing flow. In software development, Kanban boards are commonly used to represent tasks visually, allowing teams to track progress in real time and quickly identify bottlenecks or areas needing attention.