The term health insurance is commonly used in the United States to 
describe any program that helps pay for medical expenses, whether 
through privately purchased insurance, social insurance or a 
non-insurance social welfare program funded by the government. Synonyms 
for this usage include "health coverage," "health care coverage" and 
"health benefits."  In a more technical sense, the term is used to 
describe any form of insurance that provides protection against the 
costs of medical services. This usage includes private insurance and 
social insurance programs such as Medicare, but excludes social welfare 
programs such as Medicaid. In addition to medical expense insurance, it 
also includes insurance covering disability or long-term nursing or 
custodial care needs.  The US health care system relies heavily on 
private and not-for-profit health insurance, which is the primary source
 of coverage for most Americans. According to the United States Census 
Bureau, approximately 85% of Americans have health insurance; nearly 60%
 obtain it through an employer, while about 9% purchase it directly. 
Various government agencies provide coverage to about 28% of Americans 
(there is some overlap in these figures).  In 2007, there were nearly 46
 million people in the US (over 15% of the population) who were without 
health insurance for at least part of that year.[2] Over 1 million 
workers lost their health care coverage in January, February and March 
2009. Approximately, 268,400 more workers lost health care coverage in 
March 2009 than in March 2008. Proving that today, that number is 
markedly higher as many workers who have lost their jobs have also lost 
their employer-provided health insurance.[3] The percentage of the 
non-elderly population who are uninsured has been generally increasing 
since the year 2000. There is considerable debate in the US on the 
causes of and possible remedies for this level of uninsurance as well as
 the impact it has on the overall US health care system. (see Health 
care reform in the United States).