This video, titled "A 10-Minute Overview of Japan's Health Insurance System and How It Works" (10分でわかる健康保険制度の概要と仕組み), was released by "takopetty" (タコペッティ).
This is an easy-to-understand summary of Japan's health insurance system.

There are several types of social insurance in Japan, including health insurance, long-term care insurance, worker's accident insurance, unemployment insurance, and annuity insurance.
If you are a company employee, the company pays the premiums, and if you are working as an individual, you pay the premiums yourself.
By paying the premiums, you have a system in place to get support in case of an emergency.

Money, such as high-cost medical expense benefits and injury and illness allowance can be received if you apply for them, so you can rest assured that you'll be able to apply and receive money the right way if the situation arises.