Editing Flashcard (section)

== Psychology ==
Flashcards specifically exercise the mental process of [[active recall]]: given a question, one must produce the correct answer. However, many have raised several questions regarding optimal usage of flashcards: how does one precisely use them, how frequently does one review, and how does one react to errors, either complete failures to recall or partial mistakes? Various [[#Systems|systems]] have been developed, mostly based around [[spaced repetition]], the technique of increasing time intervals between reviews whenever a card is recalled correctly.

=== Spaced repetition ===
{{Main|Spaced repetition}}Spaced repetition is an [[evidence-based learning]] technique which incorporates increasing time intervals between each review of a flashcard in order to harness the [[spacing effect]]. Newly introduced and more difficult flashcards are shown more frequently, whereas older and less difficult flashcards are shown less frequently. The use of spaced repetition has been shown to generally increase one's rate of learning.<ref>{{cite journal |last1=Smolen |first1=Paul |last2=Zhang |first2=Yili |last3=Byrne |first3=John H. |title=The right time to learn: mechanisms and optimization of spaced learning |journal=Nature Reviews Neuroscience |date=25 January 2016 |volume=17 |issue=2 |pages=77–88 |doi=10.1038/nrn.2015.18 |pmid=26806627 |pmc=5126970 |arxiv=1606.08370 |bibcode=2016arXiv160608370S }}</ref> Although the principle is useful in many contexts, spaced repetition is commonly applied in contexts in which a learner must memorize a large number of items and retain them in long-term memory. It is therefore often used in [[vocabulary]] acquisition amidst second language learning. Additionally, spaced repetition software has been developed to aid the learning process through a virtual format as opposed to merely a physical one.<ref>"Human Memory: Theory and Practice", Alan D. Baddeley, 1997</ref>

==== Leitner system ====
[[File:Leitner_system_alternative.svg|thumb|230x230px|In the [[Leitner system]], correctly answered cards are advanced to the next, less frequent box, while incorrectly answered cards return to the first box for more aggressive review and repetition.]]
The [[Leitner system]] is a widely used method of efficiently using flashcards. Originally proposed by the German science journalist [[Sebastian Leitner]] in the 1970s, it is a simple implementation of the principle of spaced repetition where cards are reviewed at increasing intervals.

In this method, flashcards are sorted into groups according to how well the learner knows each one in the Leitner's learning box. The learners then try to recall the solution written on a flashcard. If they succeed, they send the card to the next group. If they fail, they send it back to the first group. Each succeeding group has a longer period of time before the learner is required to revisit the cards. In Leitner's original method published in his book ''So lernt man Lernen'' (''How to learn to learn''), the schedule of repetition was governed by the size of the five partitions in the learning box, which were 1, 2, 5, 8, and 14 centimeters, respectively. The learner only reviewed some of the cards in a section whenever it became full, subsequently moving them forward or backward depending on whether they remembered them.

====Software====
[[File:Anki flashcard question and answer math.gif|thumb|Example of a virtual flashcard: using [[list of flashcard software|flashcard software]] [[Anki (software)|Anki]] to review a mathematical formula. First, only the question is displayed. Then the answer is displayed too, for verification.]]{{main article|List of flashcard software}}There is a wide range of software, including [[open source]] and online services, available for creating and using virtual flashcards as a learning aid.