A more thorough explanation:

Single payer is a healthcare system where all medical fees are collected for a group of people and paid to their doctors from a single government source. This group of people can be small, like only people over 65 years old, or it can be universal, meaning every person in a certain area.

• Medicare: In the United States, Medicare is a single payer system for people over 65 years old. The government collects fees from taxpayers and pays doctors for medical services for eligible individuals.
• Canada: Canada has a universal single payer healthcare system. The government collects fees from taxpayers and pays doctors for medical services for all citizens and permanent residents.

These examples illustrate how single payer systems work by having a central source of payment for medical services. In both cases, the government collects fees and pays doctors for medical services. This eliminates the need for individuals to pay for medical services out of pocket or through private insurance companies.