The Forgetting Curve is a concept developed by German psychologist Hermann Ebbinghaus in the late 19th century. It represents how information is lost over time when there is no attempt to retain it. Essentially, as soon as we learn something new, we begin to forget it. The speed at which we forget depends on various factors such as the complexity of the information, the relevance to us, and whether or not we revisit that knowledge.

Ebbinghaus discovered that memory retention declines exponentially over time—meaning that in the hours and days following new learning, without reinforcement, we lose most of what we’ve learned. However, with proper review and reinforcement, we can dramatically slow down this rate of forgetting and strengthen our memory.

To put it simply: we forget things quickly unless we actively work to remember them.