CNN  — 

Isolation, quarantine, shelter in place. These are terms we’re hearing a lot of these days, as authorities try to stem the spread of the novel coronavirus that’s sweeping the United States and the rest of the world.

They’re not the same thing, though they all have the goal of keeping others from getting infected. But what do they mean, exactly?

Here are some brief explanations.

Quarantine

This is for people who may have been exposed to the virus. They are asked to stay at home, or as in the case with people who were repatriated from China to the United States, to stay in a provided facility.

They’re required to be in quarantine for 14 days. After that, people who still don’t test positive for the virus no longer have to be in a contained environment.

Some people may choose or be asked to self-quarantine, meaning they do it voluntarily because they think they may have been exposed or they are being cautious.

Governments – federal, state and local – can order quarantines, and in fact, those repatriated from China were under a federal quarantine order.

That’s only done in extremely rare situations, though. The last time it was ordered on a large scale was during the Spanish Flu