Crc Cards require a little explanation.
Here are a few pages touching the subject:
- BezelMenu
- CrcCardSoftware
- CrcCards
- CrcCardsAreCognitive
- CrcDescribesScenarios
- CrcDoesntCaptureAnything
- CrciCards
- SketchesOfThought
- StoryCard
- TheCrcCardBook
- UserStories
- WardAndKent
- WikiWikiHyperCard