Watch: Boy Screams Out the Window at Night in Sweden; Result Will Shock You!

What happens when you pop your head out of your window late at night and scream?

Chances are, a neighbor or two may complain about the disturbance. You may also receive a visit from the authorities responding to the complaint or call from a concerned citizen. Or maybe nothing will happen.

Not in Sweden, particularly where this student in a video clip uploaded by Reddit user BuffPiggy.

The Redditor in question had posted a 2-minute clip that showed him screaming outside his window and getting a series of screams echoing into the night in return.

"Screaming into the dark of night isn't a source of unsettlement, it's a point of pride," MTV explained. This phenomenon, usually happening at 10 p.m., is called The Flogsta Scream, which is "one of those totally legitimate Swedish things that makes no sense to outsiders such as us."

According to The Huffington Post, it's not known why this event happens. "Some say it's to remember a student who committed suicide in the 1970s, others say it's to calm the nerves of exam season," the publication said.

MTV explained further that the activity began in the 70s, when "students in the Flogsta neighborhood of Uppsala, Sweden started sticking their heads out the window at 10PM every night to scream into the darkness."

"Apparently it began in the 1970s and has been going on - no joke - every single night since it started," the site added.

The video has generated comments from viewers, with one from Norway sharing that saying hello to his neighbor earns him a "frightened" look.

"He says nothing back and hurries along. It is my goal to make him say hello back to me, so every time I try to appear more happy and nice when I say it. Sadly though his fear of acknowledging me seems to increase exponentially," the commenter said, as noted by The Huffington Post.

News.com.au noted that some users from American cities said that "doing the same in their hometown would get you screamed at in a very different way - or perhaps even shot."

Flogsta has many apartment blocks with Uppsala University students for residents. It is said that although the screamfest happens nightly, it "usually only lasts for about five minutes, and is loudest on weekends."

However, not all Swedish know about this tradition. One who transferred to Flogsta got confused by the phenomenon, describing his reaction as "close to terror," News.com.au said.

"The screaming now also happens in student area of Lappkarrsberget in Stockholm and in Lund, southern Sweden," the site said.

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