what is the difference between health insurance and a health plan?

I've been trying to find some medical health insurance.Why does some companies say health insurance others say health plan?
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Health Insurance is: insurance against expenses incurred through illness of the insured. Health plan: a Choosing between health plans is not as easy as it once was. Although there is no one "best" plan, there are some plans that will be better than others for you and your family's health needs. Plans differ, both in how much you have to pay and how easy it is to get the services you need. Although no plan will pay for all the costs associated with your medical care, some plans will cover more than others. Go here to learn more...good luck
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