Spaced repetition is a learning technique that involves reviewing information at increasing intervals over time. This method helps reinforce memory retention by taking advantage of the brain's natural forgetting curve, allowing learners to recall information more effectively. By spacing out study sessions, individuals can improve their long-term retention of facts, vocabulary, or concepts. Tools like flashcards or apps, such as Anki, often utilize spaced repetition algorithms to schedule reviews, ensuring that learners focus on material just before they are likely to forget it.