It started in Central Java, an Indonesian province east of Jakarta. Groups of youngsters stand by the side of the road, shouting and holding signs reading, "om telolet om!" — a phrase The Jakarta Post says loosely translates to "Driver, honk, driver!"

A video of children in the town of Jepara was posted on Facebook late last month and now has more than 2 million views. Many of the comments are along the lines of "it's a simple game, but it makes them happy."

So why are the kids clamoring for bus drivers to honk?

The Indonesian buses don't just have ordinary horns — they're melodic, playing brief tunes that delight the crowds of children gathered to hear them. And they don't all play the same tune. Even some grown-ups are getting in the spirit.

This week on Twitter, popular DJs such as Zedd and Firebeatz started tweeting about the phenomenon, and sampling the bus horn sounds into their music. Billboard looked into the trend, predicting that dance music enthusiasts will be hearing much more of the bus horn tunes. The DJ Marshmello tweeted a picture of an "om telolet om" T-shirt design with the caption, "coming soon."

As for the kids who started it all, they might not be able to play their game for much longer. Indonesian Transportation Minister Budi Karya Sumadi has called for bus drivers to ignore the pleas to honk their horns, because he worries about the safety of kids gathered in high-traffic areas. However, the Post reports that Budi "appreciates young people's creativity" and is considering an official "Bus Telolet" contest to celebrate the unique horn sounds.

In the event the horn honking is effectively silenced, a number of apps in the Google Play store offer different horn sounds on demand. One called Klakson Telolet promises a "big bus horn," and another offers a game called "Telolet Om," challenging players to "become the best bus driver!"

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