PPO (Preferred Provider Organization) - A type of insurance plan that offers more extensive coverage for the services of healthcare providers who are part of the plan's network, but still offers some coverage for providers who are not part of the plan's network. PPO plans generally offer more flexibility than HMO plans, but premiums tend to be higher.
California developed a solution to assist people across the state and is one of the few states to have an office devoted to giving people tips and resources to get the best care possible. California's Office of the Patient Advocate was established July 2000 to publish a yearly Health Care Quality Report Card[37] on the top HMOs, PPOs, and Medical Groups and to create and distribute helpful tips and resources to give Californians the tools needed to get the best care.[38]

Carrin, Guy; James, Chris (January 2005). "Social health insurance: Key factors affecting the transition towards universal coverage" (PDF). International Social Security Review. 58 (1): 45–64. doi:10.1111/j.1468-246x.2005.00209.x. Retrieved 10 March 2013. Initially the health insurance law of 1883 covered blue-collar workers in selected industries, craftspeople and other selected professionals.6 It is estimated that this law brought health insurance coverage up from 5 to 10 per cent of the total population.
Nearly one in three patients receiving NHS hospital treatment is privately insured and could have the cost paid for by their insurer. Some private schemes provide cash payments to patients who opt for NHS treatment, to deter use of private facilities. A report, by private health analysts Laing and Buisson, in November 2012, estimated that more than 250,000 operations were performed on patients with private medical insurance each year at a cost of £359 million. In addition, £609 million was spent on emergency medical or surgical treatment. Private medical insurance does not normally cover emergency treatment but subsequent recovery could be paid for if the patient were moved into a private patient unit.[44]

The state passed healthcare reform in 2006 in order to greater decrease the uninsured rate among its citizens. The federal Patient Protection and Affordable Care Act (colloquially known as "Obamacare") is largely based on Massachusetts' health reform.[39] Due to that colloquialism, the Massachusetts reform has been nicknamed as "Romneycare" after then-Governor Mitt Romney.[40]
The universal compulsory coverage provides for treatment in case of illness or accident and pregnancy. Health insurance covers the costs of medical treatment, medication and hospitalization of the insured. However, the insured person pays part of the costs up to a maximum, which can vary based on the individually chosen plan, premiums are then adjusted accordingly. The whole healthcare system is geared towards to the general goals of enhancing general public health and reducing costs while encouraging individual responsibility.
HMO (Health Maintenance Organization) - Offers healthcare services only with specific HMO providers. Under an HMO plan, you might have to choose a primary care doctor. This doctor will be your main healthcare provider. The doctor will refer you to other HMO specialists when needed. Services from providers outside the HMO plan are hardly ever covered except for emergencies. 
Insurance plans with higher out-of-pocket costs generally have smaller monthly premiums than plans with low deductibles. When shopping for plans, individuals must weigh the benefits of lower monthly costs against the potential risk of large out-of-pocket expenses in the case of a major illness or accident. Health insurance has many cousins, such as disability insurance, critical (catastrophic) illness insurance, and long-term care (LTC) insurance.
As of 2014, more than three-quarters of the country’s Medicaid enrollees were covered under private Medicaid managed care plans, and 31 percent of Medicare beneficiaries were enrolled in private Medicare Advantage plans in 2016. However, the funding for these plans still comes from the government (federal for Medicare Advantage, and a combination of state and federal funding for Medicaid managed care).
Health insurance in the United States is any program that helps pay for medical expenses, whether through privately purchased insurance, social insurance, or a social welfare program funded by the government.[1] Synonyms for this usage include "health coverage", "health care coverage", and "health benefits". In a more technical sense, the term "health insurance" is used to describe any form of insurance providing protection against the costs of medical services. This usage includes private insurance and social insurance programs such as Medicare, which pools resources and spreads the financial risk associated with major medical expenses across the entire population to protect everyone, as well as social welfare programs like Medicaid and the Children's Health Insurance Program, which both provide assistance to people who cannot afford health coverage.
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