Critical Infrastructure (CI) comprises physical and cyber assets vital for the smooth functioning of societies and nations across the globe. The sectors that make up critical infrastructure differ from one country to another. For example, the USA considers 16 sectors to be vital as opposed to 13 in the UK. The disruption or damage of CI can have severe direct and indirect effects.
If you handle, process or store credit cards in any manner, you are required to comply with PCI DSS, or Payment Card Industry Data Security Standards. This is a set of LEGAL requirements you must abide by to maintain a secure environment. If you violate them, you will incur serious fines and fees.