Can you help me understand health insurance in the UK?

My parents would like to travel to US from the UK for a vacation – health insurance question?

UK: Is there any dental insurance that will cover braces?

Taxation for the Self-Employed

Where can i find a list of insurance terminology and definitions?

What is the difference between Health Insurance and Health care Program?

health insurance. I want to visit the UK and france for a week?

Is UK NHS coverage considered as crediable coverage for US insurance?

Benefits of Income Protection Insurance

Life Insurance Uk: Because Your Dependents Need Your Care