A single-payer system is a type of healthcare financing where a single public or quasi-public agency handles health care costs for all residents. In this model, the government collects taxes to fund healthcare services, ensuring that everyone has access to necessary medical care without direct charges at the point of service. This system contrasts with multi-payer systems, where multiple private and public insurers manage healthcare payments. Countries like Canada and the United Kingdom utilize single-payer systems, aiming to reduce administrative costs and provide universal coverage, thereby improving overall public health outcomes.