8. Spaced Interval Repetition
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If you've ever had to memorize something, you are probably familiar with spaced interval repetition (SIR). SIR is a learning technique that uses repeated testing over increasing intervals until whatever you're trying to memorize finally sticks. So you test yourself a lot at first, then less and less over time. It sounds really basic but SIR is a well-supported way to get the most out of your memory – and a reason there are so many new smartphone apps that follow this technique.