Patient Protection and Affordable Care Act (PPACA, ACA or Obamacare)

ACA exchanges

The ACA created state-run health insurance exchanges, or online marketplaces, for patients who don't receive coverage from an employer to research and apply for an insurance plan. Exchanges are accessible through websites, call centers, and in-person assistance, and from the federal government's www.healthcare.gov website.

People who apply for insurance on an exchange find out whether they qualify to save money on a subsidized plan and if they are eligible for Medicaid or the Children's Health Insurance Plan (CHIP), which is part of the Medicare Access and CHIP Reauthorization Act of 2015, which established a framework for value-based care.

What the ACA does

The ACA bars insurance companies from denying benefits to patients with pre-existing medical conditions. It also allows people under age 26 to get insurance coverage under their parents' plan. Under the law, patients who enroll in an insurance plan also are allowed to be treated by any primary care provider and receive a summary of their benefits, written in simple language with a glossary of frequently used medical terms.

Public opinion and opposition

The law has been one of the most controversial political issues of the 21^st century, generally dividing the country across ideological lines, with liberals supporting it and conservatives opposing it. The ACA has so far survived two repeal attempts by President Donald Trump -- who campaigned against the law -- and a Republican-dominated Congress. In particular, the requirement that all citizens carry health insurance -- the so-called individual mandate -- has faced and is continuing to meet strong opposition from many conservatives. Soon after taking office on Jan. 20, 2017, Trump signed his first executive order as president directing federal agencies to "waive, defer, grant exemptions from or delay" any part of the Patient Protection and Affordable Care Act that imposes a financial or regulatory burden on those affected by it. However, the law remains mostly intact and in effect.