Spaghetti Plot is a method of viewing observations to visualize possible flows through systems. Flows depicted in this way appear like noodles, hence the coining of this term Spaghetti Plot.

This method of statistics was first used to track routing through factories. Visualizing flow in this way can cut inefficiency within the flow of a system. In regards to animal populations and weather buoys drifting through the ocean, they are drawn to study distribution and migration patterns. Within meteorology, these diagrams can help determine confidence in a specific weather forecast, as well as positions and intensities of high and low pressure systems. They are composed of deterministic forecasts from atmospheric models or their various ensemble members. Within medicine, they can illustrate the effects of drugs on patients during drug trials.

Spaghetti plot is one of the main tools used to lean the system especially focusing on the layouts in the shop-floor. In process flow, focus should be on the number of touch points. Spaghetti plot gives a visual indication of the inefficiencies in the system caused by the layouts and flow. The aim is to focus on reducing the number of touch points and travel time in the process by optimizing the layout.