The Marb(e)lous BB84: Exploring Tangible Interfaces to Explain Quantum Key Distribution to Adults

We explored the use of tangible interfaces to explain Quantum Key Distribution (QKD) - an inherently complex but increasingly important cybersecurity topic - to adults. Tangible interfaces can support the understanding of complex topics. Yet their role in cybersecurity remains underexplored, despite persistent demands for security awareness and Quantum Computing education. To address this, we applied a participatory approach: (1) exploring current explanations through a survey of QKD professionals ( N = 8) and analysis of popular YouTube videos, (2) conducting ideation workshops ( N = 9) to derive design considerations, (3) developing the Marb(e)lous BB84 educational interface, and (4) comparing its benefits and challenges with slides and the most popular video ( N = 43). We found that supporting exploration and playfulness is key, as well as rooting explanations in real-world scenarios. Our tangible interface was perceived as highly engaging and attractive. Finally, we contribute design implications for cybersecurity explanation interfaces targeting adults.