Insurance card in Japan

Insurance is a term in law and economics. It is something people buy to protect themselves from losing money. People who buy insurance pay a "premium" (often paid every month) and promise to be careful (a "duty of care"). In exchange for this, if something bad happens to the person or thing that is insured, the company that sold the insurance will pay the money back. (However, there are some times when the company will not have to pay the money back, such as if the person was not careful.)