Cybersecurity is an important topic which is often viewed as inaccessible due to steep learning curves and a perceived requirement of needing specialist knowledge. A number of knowledge bases have been developed to inform and underpin cybersecurity education and training. Although they may be a useful learning resource for providing key cybersecurity knowledge, their primary purpose is to be used by those who are already knowledgeable in cybersecurity to develop further but remain too complex for those with little-to-no knowledge of cybersecurity. As a solution to these two issues, we propose the use of a card deck to provide introductory cybersecurity knowledge that supports learning and discussion. Upon evaluation in two user studies, we found that 80% of the participants agreed the cards provided them with introductory knowledge of cybersecurity topics, and 70% agreed the cards provided an interface for discussing topics and enabled them to make links between attacks, vulnerabilities and defences.