Karda is an open-source flash card program for the desktop and the web, under development by Bruce Webber and timonator. Instead of presenting the user with a single word, Karda will present the user with a series of flashcards lined up simultaneously to form a grammatical Lojban sentence. Matt Arnold suggested the name, which is the Lojban word for "card", and created a requirements demo.
Karda will be somewhat similar to SuperMemo, but will be open-source and cross-platform, using Python and wxPython. The existing open-source Python-based spaced-repetition software, Mnemosyne, is fine software for what it does, but is not conveniently accessable. With Karda, Lojbanists can devote time to memorization almost anywhere, and have their progress backed up to the web.
Every day the software looks at the list of words that are coming up for review, and selects sentences from its database (generated by the pixra game) that will include all of them at least once. The software should track the user on how well he or she remembers each individual word, but present it in sentences so
that the user absorbs an understanding of grammar similar to how people absorb it from usage.
Karda tracks each word as two "facts": you are given the Lojban word and are asked for the English gloss, or given the English gloss and asked for the Lojban word. It tracks them as if they were separate
flashcards because the user is likely to be better at one of them than at the other and would need a different amount of repetition. But it knows that in a given sentence, it can test each word either way.
Bruce Webber set up the project at karda.org. There's a link from the home page to [http://trac.karda.org/|Trac), the source code management system for this project. Subversion is set up for version control. If you would like participate, please let Bruce know and he will set up a Trac user ID for you.
In Supermemo, you often get the feeling that you've already forgotten some of the most difficult cards you've worked on today. You know they need more work, but they are gone from the list and you can't remember which ones they are.
Current spaced-repetition flashcard programs operate on a 24-hour iteration. What if it was a lot more often than that? Karda could figure out how many hours or minutes it takes the user to forget something, instead of days. In the place where it used to record days, it could record the day, hour and minute when a card is committed, when it's tested on, and when it's drilled, and trigger recurrences after a certain number of hours and minutes have passed.
Of course, it would have to require the user to enter what time zone they are in, so it won't count the time they spend sleeping.
On the first day that you work on a card, you've probably forgotten it already. Repetitions in certain circumstances have been a waste of time. You can't retain what you never memorized to begin with. So it would be great to test you on it an hour after you commit the card, then two hours after that if you pass it, then if you pass it four, then eight, sixteen and so forth with every successful test. It shrinks the interval when you fail.
Maybe it could even notice when you drill on a card mere moments after you failed it in a test or drill, and make you wait until I've retained it for a meaningful amount of time before letting you drill on it and pass. For instance, ten minutes.