One “horrible” summer in 1993: Unable to play with her daughter Sara, then 7, because of her myasthenia gravis, an autoimmune disorder that causes muscle weakness, a Florida inventor named Catherine Hettinger invents a prototype of a fidget spinner as way to bond with her daughter, Hettinger recently told the Guardian.

1997: Visions of Rubik’s Cubes, Koosh balls and Pet Rocks presumably dancing in her head, Hettinger goes to Washington to secure a patent for the toy.

1997-2015: All in all, a pretty slow couple of decades on the fidget-spinner front. After Hasbro declines to market Hettinger’s invention, the patent expires in 2005. Small manufacturers, meanwhile, begin to market endless variations of the spinner, often as a therapeutic aid for children with attention deficit hyperactivity disorder, anxiety or autism, to help them focus and relieve stress. Most are three-prong or snowflake-shaped devices made of plastic or metal and fitted with ball bearings, allowing them to spin between users’ fingertips. No one so far has explained why this is considered fun.

September 2016: While spinners are nothing more than a Detroit-based soul act from the early 1970s to most people, early-adopter entrepreneurs are beginning to sense a potential fidget-based gold rush. In Denver, two twenty-something brothers, Mark and Matthew McLachlan, seek to raise $15,000 on Kickstarter for their “Fidget Cube.” They end up attracting more than $6 million. “We checked out what tools were available for fidgeting,” the founders told Adweek, “and we couldn’t find any that we’d feel truly comfortable using in a professional setting.”

Dec. 23, 2016: The hype train begins chugging. Just in time for Christmas, Forbes declares fidget spinners “the must-have office toy for 2017,” observing that stressed-out executives whose fingers are “a raw, bloody mess” because of “boredom-induced nail-biting” are trading their stress balls for fidget spinners like MD Engineering’s Torqbars, priced from $129.99 to $259.99 but which begin selling for as much as $400 on eBay, because of their limited availability. It’s like a new iPhone for those who do not actually require their gadgets to do anything.

March 22: YouTube, along with Reddit, is filling up with videos on fidget-spinner reviews, hacks, and tricks. “Fidget spinning is a lifestyle,” David King, an Australian tech blogger, says in his video, “Fidget Spinner Tricks With a Professional Fidgeter,” which has been viewed more than 3 million times. He was kidding. We think.

March 31: Lest you be confused, the fidget spinner is not just a child’s toy for grown-ups. Children love them too, according to The Boston Globe, as fidget spinners have apparently supplanted recent fads like bottle-flipping and homemade slime as a teacher nuisance. “When we got back from Christmas break, a couple of kids had them, then a couple more kids had them, and then they were definitely en vogue,” one New Hampshire schoolteacher said.

April 10: It’s not a party until the celebrities show up. InStyle recounts how Gwyneth Paltrow’s son, Moses, recently celebrated his 11th birthday by being given “a set of cool new fidget spinners before spending a sun-filled day at Legoland in California with friends and his proud mama.”

April 20: As school districts around the country ban these focus tools for being too, yes, distracting, a New York schoolteacher named Cristina Bolusi Zawacki takes to Working Mother to denounce fidget-spinners: “Let’s stop with the flowery euphemisms. It’s a toy and I hate it. I actually have a visceral reaction when they emerge from a pencil case or pocket, like a sadistic version of Pavlov’s bell experiment.”

May 2: The backlash is in full effect. In an article called “Are Fidget Spinners a Scam?” Britain’s Daily Mail quotes Dr. Mark Rapport, the director of the Children’s Learning Clinic at the University of Central Florida’s department of psychology, as saying that “using a spinnerlike gadget is more likely to serve as a distraction than a benefit for individuals with ADHD.”

May 4: What backlash? Fidget-spinners occupy 17 of Amazon’s 20 best-sellers in the Toys & Games category (and fidget cubes account for two more). A Google Trends chart of the search term looks like a hockey stick.

May 5: Hettinger still has not seen a dime from any of this, at least since the 1990s, when she sold a few thousand spinners at fairs in Florida, she told Money. But that could change. Hettinger, now 62, plans to start her own Kickstarter campaign for a “classic” spinner soon.

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