The holiday began on the campus of the University of Virginia in 2002, when a group of students set up a stand giving away free high-fives in the middle of a quadrangle.
"We discovered two things," Greg Harrell-Edge, executive director of the National High Five Project and one of the original UVA group, told PEOPLE. "One, it's real fun to give away high fives all day. Two, we got to see it spread virally in real time."
The event became a yearly tradition, and soon the likes of Jimmy Kimmel and Today were showing up to cover UVA's high-five fest. After graduation, the friends used the day as an opportunity to stay in touch, and a few years ago they added a charitable giving component – they've since raised nearly $50,000.
In the early years, Harrell-Edge and company were often asked who had invented the high five.
"We always thought it was a silly question," Harrell-Edge said. "Who invented the handshake?" In truth, they believed there was no answer to the question, so they made up a story and picked the name of former college athlete Lamont Sleets at random, inventing a fictional backstory that singled him out as the creator.
They weren't completely wrong with their assumption. The high five's older cousin, the low five, has a far murkier backstory, emerging out of the Jazz Age without easy explanation. But the high-five has several notable claims of parentage. Some, like that of Magic Johnson, are easily disproved, but a 2011 ESPN Magazine story narrowed the field down to two likely pairs of candidates, each with a valid claim. One took place on the baseball diamond, the other on a basketball court.
The Inventor of the High-Five?
On the last day of the 1977 regular season, the Dodgers were playing the Houston Astros at home. In the bottom of the sixth, outfielder Dusty Baker hit a home run to tie the game at 2, and as he finished rounding the bases, he saw his teammate Burke waiting with arm aloft.
"His hand was up in the air, and he was arching way back," Baker told ESPN. "So I reached up and hit his hand. It seemed like the thing to do."
Up next, Burke hit his own home run – the first of his career – to put the Dodgers in the lead. Baker returned the favor with a high five of his own. Though the Dodgers eventually lost the game, the high-five stuck. In a few short years, it had become enough of a clubhouse staple that the team sold T-shirts featuring two hands meeting in the air. Burke claimed it as his invention for the rest of his life.
After a controversial trade to the Oakland As, an early retirement and a long battle with drug addiction, Burke died of AIDS in 1992. His family told ESPN they see the high five as one of his greatest legacies.
Tsugufumi Matsumoto / AP
"He just said, 'Give it up high,'" Brown told the IUS Horizon in 2013. "Remember, you're talking about one 6' 8" guy and another 6' 8" guy – why are we gonna do low fives?"
Brown remembers being energized by the high five, and he says the momentum of the act inspired the team's high-flying success. Throughout their championship season, Smith and Brown repeated the high five after making a big play – Brown always using his left hand since he'd had the thumb amputated on his right – and, since Burke and Baker's fateful game had not been televised, it was likely that the Louisville basketball high fives were America's first introduction to the famous slap.
Unfortunately, we can't sit all the claimants down to separate fact from legend. Smith died of a heart attack a year after Burke passed away. It's likely, as the UVA crew assumed, that nobody truly invented the high-five; humans have been slapping palms above the waist for decades without a name to call the act, including at a memorable moment in the 1960 French New Wave film Breathless.
"We hate the idea that we took these guys' shine," Harrell-Edge told PEOPLE.
Still, the holiday's organizers see the day as a way to spread the same intense joy that Burke and Smith experienced on the field of competition into the mundane moments of everyday life. And they say there are health benefits to the high five, a less germy alternative to the handshake.
"If the handshake was outlawed, there'd be fewer colds, fewer flus," Harrell-Edge argued, though he admitted the team had not found a doctor willing to go on the record to confirm their theory. And for the first time ever, they're selling gear for the fundraiser: T-shirts that read "I give free high fives, try me." If you end up participating, why not use the occasion to try out these advanced high-five techniques?