Table of Contents
Anki is a program which makes remembering things easy. Because it is a lot more efficient than traditional study methods, you can either greatly decrease your time spent studying, or greatly increase the amount you learn.
Anyone who needs to remember things in their daily life can benefit from Anki. Since it is content-agnostic and supports images, audio, videos and scientific markup (via LaTeX), the possibilities are endless. For example:
There are two simple concepts behind Anki: active recall testing and spaced repetition. They are not known to most learners, despite having been written about in the scientific literature for many years. Understanding how they work will make you a more effective learner.
Active recall testing means being asked a question and trying to remember the answer. This is in contrast to passive study, where we read, watch or listen to something without any output. Research has shown that active recall testing is far more effective at building strong memories than passive study. There are two reasons for this:
You have probably encountered active recall testing in your school years without even realizing it. When good teachers give you a series of questions to answer after reading an article, or make you take weekly progress-check tests, they are not doing it simply to see if you understood the material or not. By testing you, they are increasing the chances you will be able to remember the material in the future.
You don’t need to leave it up to teachers, however. Consider a language learner who wants to memorize a list of 20 Indonesian numbers, like:
1 = satu
2 = dua
3 = tiga
Many students will look at each line in turn, concentrating on it for a few seconds before moving on. This is passive learning, and so the results will not be great. However, if you simply cover the right-hand side and check if you recall each word, you’ll find your initial memories are stronger.
Active recall testing can make for stronger initial memories, but it’s only part of the solution to learning efficiently.
Even with active recall testing, if you wait too long before testing again, you’ll find you’ve forgotten most of the material you tried to learn. This can be very demotivating, as it can feel like no progress is being made towards your goals. In order to avoid this disappointment, it’s essential to review previously learnt material.
Despite the importance of review, it is often overlooked by learners. Part of the reason for this is that reviewing was traditionally difficult. If you have a page with 50 new words on it and you learn them in one day, some words will fall from your memory the next day, others a few days after that, and others may last a few weeks or more. It is difficult to return to the page and review only the words you’re about to forget.
Traditional paper flashcards make it easier to acquire material than a single page with a list of words, since you can separate the cards into "known" and "not-known" piles. They don’t make it very easy to review the material in the following weeks, however.
The spacing effect was reported by a German psychologist in 1885. He observed that we tend to remember things more effectively if we spread reviews out over time, instead of studying multiple times in one session. Since the 1930s there have been a number of proposals for utilizing the spacing effect to improve learning, in what has come to be called spaced repetition.
One example is in 1972, when a German scientist called Sebastian Leitner popularized a method of spaced repetition with paper flashcards. By separating the paper cards up into a series of boxes, and moving the cards to a different box on each successful or unsuccessful review, it was possible to see at a glance a rough estimate of how well a card was known and when it should be reviewed again. This was a great improvement over a single box of cards, and it has been widely adopted by computerized flashcard software. It is a rather rough approach however, as it can’t give you an exact date on which you should review something again, and it doesn’t cope very well with material of varying difficulty.
The biggest developments in the last 30 years have come from the authors of SuperMemo, a commercial flashcard program that implements spaced repetition. SuperMemo pioneered the concept of a system that keeps track of the ideal time to review material and optimizes itself based on the performance of the user.
In SuperMemo’s spaced repetition system, every time you answer a question, you tell the program how well you were able to remember it - whether you forgot completely, made a small mistake, remembered with trouble, remembered easily, etc. The program uses this feedback to decide the optimal time to show you the question again. Since a memory gets stronger each time you successfully recall it, the time between reviews gets bigger and bigger - so you may see a question for the first time, then 3 days later, 15 days later, 45 days later, and so on.
This was a revolution in learning, as it meant material could be learnt and retained with the absolute minimum amount of effort necessary. SuperMemo’s slogan sums it up: with spaced repetition, you can forget about forgetting.
While there is no denying the huge impact SuperMemo has had on the field, it is not without its problems. The program is often criticized for being buggy and difficult to navigate. It only runs on Windows computers. It’s proprietary software, meaning end-users can’t extend it or access the raw data. And while very old versions are made available for free, they are quite limited for modern use.
Anki addresses these issues. You are not forced to pay for it, so struggling students and teachers with budgetary constraints are not left out. It’s open source, with an already flourishing library of plugins contributed by end-users. It’s multi-platform, running on Windows, Mac OSX, Linux/FreeBSD, and some mobile devices. And it’s considerably easier to use than SuperMemo.
Internally, Anki’s spaced repetition system is based on an older version of the SuperMemo algorithm called SM2. Subsequent versions have managed to squeeze out a little more learning efficiency, but they come at the cost of greatly increased complexity, and they are more susceptible to scheduling errors in real-world use. For a more in-depth discussion of this and the differences in scheduling algorithms, see the bottom of Frequently Asked Questions.
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If you want to run Anki from a USB stick, follow the instructions on Frequently Asked Questions. |
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If you want to run Anki from a USB stick, simply drag it to the USB stick instead. |
The currently recommended method is to install Anki from source, or use the deb on the Anki website if you are a Debian/Ubuntu user. You may find a version of Anki is included with your distribution, but at the time of writing a number of distros include a very old version of Anki that has a number of known bugs.
Installing from source:
.tar.gz
file from Downloads.
README
file for instructions.
Installing on Debian/Ubuntu:
.deb
file from Downloads.
sudo dpkg -i <downloaded file>
Anki uses cards to help you with active recall testing and spaced repetition. Each card is a virtual flashcard with a question and answer. These cards are stored together in a file called a deck. You can have one big deck or keep separate decks for separate subjects.
Most of your time in Anki will be spent reviewing these cards, but to get started we first need to add some. You can add cards by typing them in yourself, copying & pasting them from some online resource, importing them from a text file, or you can use a deck someone else has shared.
To create your own deck:
To open a shared deck:
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You are not limited to one deck. You can see a list of your decks by
clicking on |
If you have downloaded a shared deck, this step is optional.
To add a new card to your deck:
You’ll see a screen like the following:
Front, Back and Add are the important elements for now - the rest we’ll return to later. Front is a required field, so it is marked yellow until you input something. The back can be left blank, so it is not drawn in yellow.
Turning a given idea into a question and answer pair is simple once you know how.
20 rules
Imagine you’ve just heard the following sentence:
Canberra was founded in 1913.
The easiest way to test this is to make a cloze deletion.
As an alternative to steps 3 & 4, you can just press F9.
You’ll end up with:
Imagine you’re learning learning German and you hear the word bitte, meaning "please". There are a number of ways to add this to Anki.
As a word recognition card:
Put bitte on the front of the card, and please on the back. When this card appears later, you’ll need to read the German word and decide if you knew the meaning or not. Recognition cards are easy to answer and will ensure you can recognize the word when it pops up in the future.
As a word recall card:
Put please on the front of the card, and bitte on the back. When this card appears later, you’ll need to think of how to say please in German. Recall cards are more difficult to answer, but will ensure you can produce the given word yourself, rather than just recognize it. They are best used in the early stages of learning, to reinforce basic grammar and core vocabularly. As your knowledge of the language grows, recall cards become less practical, as synonyms complicate matters.
As a sentence recognition card:
You can also add the full sentence you encountered to the front of the card, optionally underlining the new word. On the back you can place a translation of the full sentence, or just the target word. Adding the full sentence takes more time, but means you’re exposed to the word in actual use.
As a sentence recall card:
Sentence recall cards should be limited to core grammar or essential phrases, as they are very difficult to answer correctly.
As a combination of the above:
It’s possible to add more than one card at once by clicking on the button at the top right of the Add Items screen. This can be useful if you’re learning a language where reading a word is non-trivial, and you want to practice both reading and producing the word.
When you have found a deck you like or entered some cards in, it’s time to start reviewing. If the Add Items screen is still open, close it by clicking on close or pressing Esc. You should see a screen entitled Study Options:
In the above example, it says there are 6 new cards today, and 6 new cards total. If you’ve downloaded a shared deck, there will probably be more than 20 new cards, but Anki will only show you 20 per day by default. You can adjust this number by changing new cards per day, but be wary of setting it too high or you’ll have many reviews to do over the next few days.
When you’re ready, click Start Reviewing. You’ll then see a screen like this:
Here you need to look at the question and think about the answer. It can help to say the answer out loud, but that is not necessary. It’s ok if it takes you a little while to recall the answer, but as a general rule if you can’t answer within 10 seconds, you should give up.
When you’re ready, click Show Answer or press the spacebar. You’ll see something like the following:
Now you need to decide how well you remembered. Anki gives you four options.