Spaced Repetition
Definition
Spaced repetition is a learning technique that schedules reviews of material at increasing intervals timed to just before you would forget it. It exploits two robust findings from cognitive psychology: the spacing effect (distributed practice beats cramming for long-term retention, documented since Ebbinghaus's forgetting-curve work) and the testing effect (actively retrieving an answer strengthens memory far more than re-reading).
In practice, flashcard systems grade each recall — the harder an item was, the sooner it comes back; easy items get pushed further out. Algorithms descended from SuperMemo's SM-2 (used by Anki and most modern apps, including WACC Buddy's Again/Hard/Good/Easy scheduler) adjust each card's interval and ease based on your ratings, concentrating your time on your weakest material.
The result is dramatically better retention per minute of study than massed review — ideal for large factual banks like interview technicals.
Why interviewers ask
IB interview prep is a memory problem at scale — hundreds of technicals that must be recallable under pressure weeks after you learned them. Spaced repetition is the evidence-based way to get there, and it is the engine behind WACC Buddy: rate honestly, review daily, and trust the scheduler rather than re-cramming what you already know.
Related terms
Interviews don't test definitions — they test recall under pressure.
Drill 1,500+ real questions with spaced repetition. Free to start — 10 reps a day on the house.