Game mechanics
Discs, clears, chains, and the rising board.
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Vocabulary
Definitions for the game, search, learning, and research results, grouped by topic.
Search and decisions
Choices, chance, and looking ahead before a move.
Browse definitionsLearning and training
Policies, teachers, and learning from played games.
Browse definitionsEvidence and results
Game samples, comparisons, and the labels on a result.
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Choose a topic to browse its terms. Each definition has a direct link, and you can find terms with the site search.