The NHS was, and largely remains, a system of medicine, intended to be "free at the point of delivery" and paid for by taxes. Private medical care remained, and remains, available in the UK.
The NHS continues to provide the vast majority of healthcare in the UK. The long-term future of the NHS and its day to day organisation are major issues in British politics. Chronic underfunding under successive goverments, combined with an exponential increase in unrealistic central directives, have led to a worsening situation of understaffing and low morale.
Contrary to popular misconception, the founding principles of the NHS called for its funding out of general taxation, not through national insurance.