In early April, the Twitter account @pepecoineth posted a photo of a cartoonish green frog wearing a red cap emblazoned with “Make Memecoins Great Again,” referring to Donald Trump’s presidential slogan.

Two weeks later, the Pepe coin, whose name comes from a popular meme co-opted by the American alt-right, was released with a total supply of 420.69 trillion coins. (The meaning of these numbers is, ahem, self-evident.) A trading frenzy ensued, and Pepe, which is “fueled by pure memetic power” and trades under the ticker $PEPE, skyrocketed in value.

In less than three weeks, the market capitalization for the memecoin—a cryptocurrency that’s typically a joke and tool for speculation—crossed $1.6 billion, according to CoinMarketCap. (It is currently hovering near $800 million.) Each coin is worth between two- to three-millionths of a dollar. Since CoinGecko began tracking it on April 18, one day after its debut, the Pepe token has increased more than 900% in price—it’s now listed on major exchanges like Crypto.com and Binance.

“Pump the frog,” an exhortation to increase the token's price, became a common refrain on Twitter, and the cryptocurrency’s Telegram group is a chaotic mishmash of memes and price talk. How did something so unabashedly worthless become so valuable?

“Feels good, man”

If there’s one meme that encapsulates the confusing twists and turns of internet culture, it’s a green frog with a preternaturally expressive face.

In 2005, illustrator Matt Furie released a web comic titled Boy’s Club that featured a frog named Pepe. The character made frequent appearances in Furie’s work. At one point, in response to a question about his bathroom habits, the character responds, “Feels good, man.”

Soon, Pepe became a popular meme, and the internet used the frog’s expressive face in almost every conceivable circumstance, including hate speech. In 2016, the Anti-Defamation League designated the meme as a hate symbol. The organization cited various online examples, including an image of Pepe saying “feels good” while wearing a Nazi stormtrooper helmet.

Furie, incensed by the co-option of his comic-book frog, launched a campaign with the Anti-Defamation League to rescue Pepe from the American alt-right. Since then, the meme has lived in comparative ambiguity. Its association with hate speech still continues, but it became a symbol.

What is a memecoin?

The Pepe token is the latest chapter in the meme’s almost two-decades-long history. But it's certainly not the first memecoin.

Dogecoin, created in late 2013 by developers Billy Markus and Jackson Palmer, was arguably the first memecoin to land on the market. They said they made it as a joke, with its name a reference the popular “doge” meme, or an image of a Shiba Inu, a particular breed of dog. As opposed to Bitcoin, a replacement for currency, or Ethereum, a decentralized computing platform, Dogecoin unapologetically had no purpose.

That didn’t stop the token from taking off in popularity, and even Elon Musk, the CEO of Twitter and Tesla, has repeatedly jumped on the doge bandwagon. Now, the cryptocurrency has a market capitalization of more than $10 billion, according to CoinMarketCap.

Since then, a flood of memecoins have saturated the market, including Shiba Inu, another dog-inspired token, and even recent additions like Good Gensler, a token that pokes fun at Gary Gensler, the chair of the Securities and Exchange Commission who’s set his crosshairs on the crypto industry writ large.

Many of the most popular memecoins, like Dogecoin and Shiba Inu, are canine-inspired. "The dogs have had their day," wrote the developers behind the Pepe token, "it’s time for Pepe to take reign."

Who's behind Pepe?

The world of crypto is a pseudonymous slurry of nicknames, numbers, and memes. And the developers of Pepecoin are similarly unknown.

They operate the @pepecoineth Twitter account, and their website has no contact information. The only clues to their activities are two press releases from mid-April: one launched from Guadelejara, Mexico, that advertises the success of the Pepe token, and another launched from London that announces the creation of another memecoin, DanGPT, “the daring twin of ChatGPT.” The name David Costla accompanies both releases.

In addition to messaging account handles associated with the Pepe token across different social media platforms, Fortune reached out to both email addresses listed on the press releases but has yet to receive a response.

In the meantime, memecoin trading has seen a dramatic uptick, according to data compiled by Dune analyst James Tolan. Pepe fervor is partly fueling the craze—many are still looking to "pump the frog"—although after crossing $1.6 billion, the token crashed to a market cap that's now closer to $800 million, according to CoinMarketCap. Pepe has traveled the internet for decades. Where he goes next is anyone's guess.