Spaced Repetition

Spaced repetition is a method for keeping information in the long term memory which can also be called memorising. The method involves flash cards. The flash cards are assigned to a number of boxes based on the subject's ability to remember the cards. The less remembered a card is, the often that card is shown. It can be considered as an activity in the metacognition domain.

It is not an integral part of the Zettelkasten method but it can be employed at least for remembering the titles of the notes.

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