Obamacare is back at the Supreme Court this morning, facing a challenge that represents the biggest legal threat to the health-care law since the justices three years ago upheld the requirement for individuals to have health insurance. The justices will hear arguments today over the financial assistance available to help people purchase health insurance. Here are some key facts to get up to speed about the case, King v. Burwell.

Source: Jason Millman, washingtonpost.com