Spaced repetition
Spaced repetition is a study technique that spaces your reviews out over increasing intervals, timing each one for the moment you are about to forget. It is the single most evidence-backed way to move facts into long-term memory with the least total study time.
Instead of reviewing everything every day (which wastes time on cards you already know) or cramming (which fades within days), spaced repetition tracks each individual card and schedules its next review just before the predicted moment of forgetting. Each successful recall pushes the next review further out — a day, then three, then a week, then a month — so the same fact takes less and less of your time while staying solid.
The technique works because of the spacing effect: memories are reinforced more durably when reviews are separated by time than when they are massed together. Retrieving a fact when it is slightly difficult — but not yet lost — produces the strongest, longest-lasting memory.
Modern spaced-repetition apps automate the scheduling so you never have to plan it. You just rate how well you recalled each card, and the algorithm does the rest.
How EverFlip does this
EverFlip schedules every card with FSRS, a modern spaced-repetition algorithm. You flip a card, rate your recall (Again / Hard / Good / Easy), and the next review is timed automatically. No planning, no signup.