Turn on the news, go online or, well, talk to anyone at all, and chances are the conversation will turn to coronavirus. And the outbreak is seriously scary, especially in densely populated areas. As NBC news reports, the virus has killed more than 20,000 people worldwide as of March 26, 2020, including more than 1,000 deaths in the United States.

The outbreak is so bad that it was declared a "Public Health Emergency of International Concern" at the end of January. And, earlier this month, the World Health Organization (WHO) declared coronavirus a "pandemic." But what exactly does that mean, how does it affect you, and how is a pandemic different from an epidemic? Read on to find out.

Upgrading the coronavirus outbreak to a pandemic might make it seem like the virus is getting more infectious. But, really, whether something is a pandemic or not all depends on how the virus spreads between people. The word "pandemic" comes from the Greek words for "all people," and means exactly that – that the virus has a global impact, with the potential to affect virtually anyone.

We already knew COVID-19 infections were found in multiple countries, but it was only recently labelled a pandemic. So what changed? Well, what separates a pandemic from an epidemic is the ability to cause a sustained infection in multiple areas globally. An epidemic, on the other hand, is more general. It means there's been a spike in an infection or disease that's unique to one country or community. A pandemic starts affecting people worldwide.

Confused? Here's an example. Let's say someone travelled to Italy, a country where COVID-19 infectious are widespread. If they got infected and traveled back home to the states, you'd technically have an international spread of the virus, since it's going from Italy to the United States. But that's still not enough to make a pandemic.

Nope, in order for something to be declared a pandemic, it has to spread among the new population, too. And that's exactly what happened – travelers were exposed to the virus abroad, brought it home, then passed it on to people in their home town. In other words, people end up with the infection even though they haven't traveled to a known affected area.

The move from an epidemic to pandemic shows just how widespread coronavirus infections are. And they're the reason that social distancing – avoiding people outside the people you live with – is so important. Because a pandemic signals that an infection can spread easily, self-isolation is the best way to both avoid getting infected and, if you have the virus, avoid passing it onto others.

So, even though it's boring, you need to stay inside as much as possible. Minimize your trips out – save it for essentials, like getting groceries – and stay at least six feet away from others to help limit the virus' spread. Wipe down potentially contaminated surfaces, like shopping cart handles, with 70% rubbing alcohol to help remove germs. And wash your hands with soap thoroughly, for at least 20 seconds, to help kill the virus.

The good news? All that time spent social distancing gives you a chance to catch up on science documentaries. Staying in also protects you and your family, and it means you're doing your part to keep this pandemic as limited as possible, which helps make everyone safer.