Stocks and Flows

Stocks and flows are two fundamental concepts used to understand systems. A stock is a quantity measured at a specific point in time, like the total amount of water in a bathtub. In contrast, a flow measures how much changes over a period, such as the water flowing in or out of the bathtub per minute. Stocks provide a snapshot of resources, while flows show the movement or change. Together, they help analyze dynamics in various fields, from economics to environmental science, illustrating how resources accumulate or deplete over time.