Back-pressure is a software engineering concept commonly used when building a system that handles high throughput of data. Its purpose is to help maintain an orderly flow of data within the system by providing feedback related to the present load within it. Back-pressure essentially helps balance going in and out of the system, thus helping ensure a continuous, successful transaction of data between components. If a system experiences an unexpected increase in load or data influx, back-pressure will create a dynamic "backlog," queuing up tasks that are waiting to be processed until the load dies down and traffic can again be handled without any drops in performance. In this way, back-pressure helps prevent overloads and consequent crashes by providing safety mechanisms for controlled influx/outflux of data within the system.