You're sitting at home, enjoying a quiet afternoon, when you hear a knock at your door. Strange. You're not expecting anyone, but maybe it's a neighbor or that package.
But when you open the door, a troop of SWAT officers outfitted in a specialized gear swarming your home and ordering you to get on the ground. They go to room, shouting commands and training their rifles.
You've just been swatted.
Andrew Finch was 28-year-old Andrew Finch, who was killed in his home in Kansas, December 201
Here's what you should know about swatting.
At the most basic level, swatting is similar to the prank calls you and your friends may have grown up.
The difference is, swatting is a prank location – usually a home – where they are committed to a horrific crime has been committed or is in progress.
 It's often carried out by the internet-savvy, such as members of online message boards, or, in Finch's case, gamers who are competing and interacting with each other in online games such as "Call of Duty."
The perpetrator might be swatting their target as part of what they believe to be a harmless prank, according to the FBI, or as an act of revenge.
Barriss, who was in California, made the call that led to Finch's death after being hit by another gamer who asked him to swat a player he'd been arguing with while playing "Call of Duty."
The gamer gave Barriss an address where the target player had once lived, but what then Finch's home.
Barriss called Wichita home, pretending to be inside the Wichita home. According to the 911 tape, Barriss said he just shot his father and was holding his gun at a gunpoint, adding, "I might just put it on fire."
The police arrived and
swatting incidents occur reach year, the fbi says, but as of 2013 to feds special agent guessed there were hundreds.
Defendants have faced federal charges before, CNN legal analyst Paul Callan said at the time of Finch's death. Swatting case poses legal
Callan said the cases are often difficult to prosecute because many of the perpetrators are juveniles who think of it as a prank or joke, and it's difficult to prove intent to cause harm.
While some pranksters might think of swatting as harmless, the FBI insisted in 2013 that it has "real consequences."
"It may cost thousands of dollars every time a SWAT team is called out," the FBI said.
CNN's Ralph Ellis, Steve Almasy and Melissa Alonso contributed to this report.