Ebbinghaus Retention Curve
The Ebbinghaus Retention Curve, also known as the forgetting curve, shows the rate at which memories are lost over time. It is named after Hermann Ebbinghaus, a pioneering researcher of human memory. He showed that we start to forget items rapidly once we stop rehearsing the material; then the rate of forgetting (or memory decay) slows. He also showed that the more time we initially spend rehearsing information, the less time it takes to relearn it later, and information we spend more time rehearsing decays at a slower rate.