To better inform the public of terrorist threats in real time, the U.S. government is adding a ‘bulletin’ category to its National Terrorism Advisory System. It even issued its first ‘bulletin’ alert, which will remain in effect until June 2016.

So what even is the National Terrorism Advisory System?

When the system was first created in 2002, the government used five color categories to warn the public of terrorism, ranging from red symbolizing severe risk to green denoting low risk. In 2011, the colors were abandoned for two simple categories: elevated and imminent risk.

An elevated alert warns of a “credible,” nonspecific threat that may or may not happen. An imminent alert is only used to warn specific areas and locations of an impending terror threat. The effectiveness of this system is unknown because the government hasn’t needed to issue a terror alert yet.

When you see a ‘bulletin’ alert, it doesn’t mean that terrorists are on their way to your front door. It is simply a means through which the government can update the public on “general trends regarding threats.” For example, if many ISIS sympathizers start targeting military recruitment centers across the country, the government would issue a bulletin to let the public know to increase security at unaffected locations.

Here’s more about the new alert from Stars and Stripes:

Homeland Security Secretary Jeh Johnson said there remains no credible, specific terror threat to the United States but that the department nevertheless issued its first bulletin to keep the public informed in a “new phase of the global threat environment.”

Wednesday’s bulletin will be in effect until June 16, 2016 and outlines much of what Johnson and other federal have said in the days and weeks since the attacks in Paris and San Bernardino.