In 1885, Hermann Ebbinghaus learned lists of nonsense syllables and tracked how fast he lost them. Memory drops steeply at first. Then it levels off. Each review resets the curve and makes the next drop slower. Drag the day marker and build a review plan to see it.
Memory over time
With reviewsNo reviewsReview day
Ebbinghaus, 1885drag the marker and add reviews
Day markerDay 7
Review plan: tap a day to study the list again.
With reviews-
No reviews-
Spacing effect: Ebbinghaus found that spaced practice (spread out) beats massed practice (crammed together). This idea is the backbone of flashcard and spaced-repetition apps today.