<b>A data-driven exploration of how children''s language learning varies across different languages, providing both a theoretical framework and reference.</b><br><br><i>The Wordbank Project </i>examines variability and consistency in children''s language learning across different languages and cultures, drawing on Wordbank, an open database with data from more than 75,000 children and twenty-nine languages or dialects. This big data approach makes the book the most comprehensive cross-linguistic analysis to date of early language learning. Moreover, its data-driven picture of which aspects of language learning are consistent across languages suggests constraints on the nature of children''s language learning mechanisms. The book provides both a theoretical framework for scholars of language learning, language, and human cognition, and a resource for future research.