October 1st, 2013 was the first time in 17 years that the federal government had to shut down, although many Americans are still confused as to what it all means.

“You’re probably not going to feel the real impact until later on down the line,” says Associate Professor of Politics and Government, Jilda Aliotta. “I mean, unless you have a 401K, in which case you probably don’t want to look at it for a while.”

What it does mean is that the federal government is officially out of money. congress failed to pass a budget for the next fiscal year, which started on October 1st, and since the government can’t pay its bills, many agencies have had to close their doors.

“A lot of the impacts depend on how long this continues,” says Aliotta. “Usually it’s very short. A day, a couple of days. The irony is it actually costs more to shut it down than it does to keep it running.”

This is only what’s called a “partial shutdown”, meaning that while the government is technically closed, some things will continue to happen.

“There are certain essential functions that congress has said will continue no matter what. Things like air traffic control. All air travel in the US won’t suddenly cease to exist.”

Other things, labeled “nonessential” like the national zoo and their panda cam, many national parks and washington area tourist attractions will close to visitors because they can’t pay the rangers and attendants to keep these areas safe. Some federal employees might even have their government issued smartphones taken away since they’re legally not supposed to be working.

But no worries, the US postal service is privately funded, so you’ll still be able to get your mail during the shutdown.