Background: Knowledge of quantum computing is arguably inaccessible to many, with knowledge of the complex mathematics involving a particular barrier to entry, creating difficulty in terms of teaching and inclusive learning for those without a high level of mathematics. Meanwhile, it is increasingly important that the knowledge of quantum technologies is accessible to those who work with real-world applications and is taught to the younger generation. Purpose: Resulting from collaborative dialogue between physicists, computer scientists, educationalists, and industrial end users, we propose the concept of quantum literacy as one means of addressing the need for transdisciplinary research in response to the complex problems that we see at the heart of issues around global sustainability. In this way, quantum literacy can contribute to UN Sustainable Development Goal 4, Quality Education. Methods: We introduce a specific puzzle visualization learning tool through which to achieve the pedagogic ends we set out with respect to quantum literacy. Visualization through puzzles can enable non-specialists to develop an intuitive, but still rigorous, understanding of universal quantum computation and provide a facility for non-specialists to discover increasingly complex and new quantum algorithms. Using the Hong-Ou-Mandel optical effect from quantum mechanics, we demonstrate how visual methods such as those made possible through the puzzle visualization tool can be very useful for understanding underlying complex processes in quantum physics and beyond and therefore support the aims of quantum literacy. Conclusion: We argue that quantum literacy, as defined here, addresses the challenges of learning within a highly bounded discipline and of access to the kind of powerful knowledge that should be more accessible to a wide group of learners. We therefore argue for the importance of addressing pedagogic issues when powerful knowledge consists of dense concepts, as well as complex and hierarchical relations between concepts, in addition to presenting a strong barrier to entry in the form of mathematics.