Blockchain technology has spawned all sorts of applications. Non-fungible tokens became popular at the end of the 2010s. "Non-fungible" means that something is unique and irreplaceable: money is fungible because it can be traded for other money resulting in the same thing. But the dollar bill that i just signed and dated on my desk is non-fungible: if i trade it for another dollar bill, it won't be the same thing. A non-fungible token (NFT) is software stored on a blockchain that certifies a digital asset to be unique. An NFT is different from copyright and trademark. There may still be copies, a countless number of copies, especially if the NFT is about music or images. The NFT says who is the owner of the original on the blockchain, but there is no difference between an original and a copied version.

Bitcoin's blockchain "invented" digital scarcity and NFT technology expanded the concept to physical and virtual assets.

NFT quickly became synonym with "collectible" in the blockchain world. And the story of collectibles on the blockchain world gets mixed with the story of memes on social networks such as 4chan. And so one needs a premise about memes that became collectibles, and Pepe is probably the most representative case. Pepe a speaking frog that originally appeared in 2006 in an web-hosted comic strip designed by Matt Furie, "Boy's Club". Somehow that speaking frog spread became a satirical joke on contemporary art within the virtual world Gaia Online. In 2008 someone started using Pepe's catchphrase "Feels good man" on a 4chan bulletin board. Created with programs like Adobe's Photoshop, variations on the original Pepe popped up in all social media. In 2012 a sad-looking Pepe became a meme on Tumblr. In October 2014 4chan users began referring to original images created for the Pepe meme as "Rare Pepes" and started "collecting" them online. These became so popular, even embraced by pop stars, that it sort of negated the original satirical meaning of Pepes. In Apr 2015 a 4chan user reacted by dumping more than 1,200 Rare Pepes on the social network. It failed to stop the craze.

Artists are frequently the deepest thinkers. Those who toyed with blockchain technology (the "cryptoartists") came up with intriguing artworks that were veritable thought experiments. The first thing to note is that cryptoart was often about memes, not necessarily about aesthetic: the meme "was" the artwork. The archetypical case was that of the "rare Pepes" for which Joe Looney created the Rare Pepe Wallet (2016) on a blockchain. The reason that Pepes became collectibles was that Pepe the Frog had become a popular meme, that thousands of people had worked on propagating the meme in more or less creative ways. The value of the "artwork" consisted in the work made by all the people who kept the meme alive. This distributed population of fans were the equivalent of cryptominers, and their activity was the equivalent of "mining" a cryptocurrency by decentralized miners. Nobody was interested in the artistic quality of the images the same way that collectors of stamps are not interested in the artistic quality of the stamp. Rhea Myers' "Mysoul" (2014) consisted in the artist's soul registered on a blockchain, thereby achieving immortality since the blockchain is immutable. Starting with Shaban Shaame's "Spells of Genesis" (2015), the "players" of virtual art galleries on blockchains were art collectors, thereby interpreting art collecting as a game and art collectors as gamers. When Marguerite de Courcelle hid bitcoins in the digital puzzle painting "Torched H34R7S" (2015), based on of William Shakespeare's poem "The Phoenix and the Turtle", she created an artwork that extended all the way to the day (three years later) that an anonymous person solved the puzzle and cashed the prize (five bitcoins). Primavera DeFilippi's "Plantoid" (2015) was a lifeform that lives and reproduces on the blockchain and feeds on cryptocurrency, thereby interpreting the blockchain as an artificial environment for artificial life. Sarah Friend's Ethereum-based game "Clickmine" (2017) makes fun of clicking and mining, both addictive activities that can get out of control, one by a person and one by a machine, and if the former can result in hypertension the latter can result in hyperinflation.

An important event took place in May 2019 at a Manhattan gallery called Lightbox: the Contemporary and Digital Art Fair (CADAF), that showcased works from cryptoartists available as NFTs.

Besides SuperRare and Rarible, digital marketplaces for NFTs soon included NiftyGateway, OpenSea, KnownOrigin, MakersPlace, etc. NFT creators would upload the file representing their NFT to one of these markets and pay to "mint" the token representing the NFT (to "tokenize" the digital art piece) on the Ethereum blockchain. This Ethereum token was as unique as the artwork itself.

History was made when in 2021 when "MetaKovan" (the code name of Indian-born Singaporean-based NFT investor and digital art collector Vignesh Sundaresan) paid $69 million for Beeple's "Everydays" NFT: for the first time ever a major auction house, Christie’s, sold a digital artwork in the form of an NFT. MetaKovan had already a history as an NFT collector through a crypto fund called Metapurse that he had co-founded in 2016. He had even hired "architects" to build the virtual city of Origin City in which a virtual gallery displayed his collection.

Originally, NFTs were static, typically a still image. Then looping GIFs emerged, and then audio NFTs, limited-edition audiovisuals experiences (typically encoded in the mp4 format) that were issued and traded as tokens on Ethereum. In 2021 four Florida kids started the Bored Ape Yacht Club, a collection of "bored ape" NFTs on the Ethereum blockchain that granted access to a private online club.

Originally, one had to purchase gas on Ethereum in order to mint an NFT. OpenSea and Rarible allowed users to create NFTs on Ethereum without paying gas. They introduced the concept of “lazy minting” by which the NFT creator puts the NFT up for sale without paying any gas fee and the fee is charged only when someone actually buys it.

By 2022 the most popular NFT platforms were: Alex Atallah's and Devin Finzer's OpenSea (2017) for the Ethereum and Polygon blockchains, which was catapulted to the top NFT marketplace in May 2019 when the twins Cameron and Tyler Winklevoss (two Bitcoin celebrities) used it to purchase a cryptopunk, Jona Wilmsmann's and Fabian Emilius' AtomicHub (2020) for the Wax and EOS blockchains, Alexander Kehaya's Holaplex (2021) for the Solana blockchain, Craig Marshall's Objkt (2021) for the Tezos blockchain, and of course Rarible for several blockchains (Ethereum, Flow and Tezos). The OpenSea had become billionaires by the end of 2021.

Here is a timeline of NFTs and cryptoart (see the history of blockchain technology for more details on the technical terms):
March 2012: Yoni Assia in Israel invents "colored coins", small denominations of a bitcoin that can represent assets such as digital collectibles, i.e. the first non-fungible tokens
January 2014: Robert Dermody, Adam Krellenstein, and Evan Wagner in New York found Counterparty, a protocol built on top of the Bitcoin blockchain that lets users make anything into a unique digital token
Apr 2014: Willa Koerner and Jenny Sharaf curate the group exhibition "Proof Of Work" at The Sub in San Francisco
May 2014: The first-ever non-fungible token (NFT), "Quantum", is minted by artist Kevin McCoy and engineer Anil Dish during Rhizome's annual 7x7 ("Seven on Seven") hackathon at the New Museum of New York
November 2014: Vancouver-based artist Rhea Myers' tokenized artwork "Mysoul" on the DogeCoin blockchain
February 2015: New York-based artist Sarah Meyohas launches "Bitchcoin", a cryptocurrency to purchase the artist's photographic prints
March 2015: The Swiss game developer Shaban Shaame issues digital trading cards on the CounterParty blockchain, later turned into the game Spells of Genesis, the first blockchain game, whose players are collectors of digital art
April 2015: North Carolina-based cryptoartist Marguerite de Courcelle hides bitcoins in the digital Bitcoin puzzle "Torched H34R7S" (2015), based on of William Shakespeare's poem "The Phoenix and the Turtle"
July 2015: Primavera DeFilippi's "Plantoid" at the Stadtwerkstatt in Linz, a lifeform that lives and reproduces on the blockchain and feeds on cryptocurrency
September 2016: Joe Looney launches Rare Pepe Wallet, a platform to trade Rare Pepe cards on Counterparty, the second platform after Spells of Genesis for blockchain-based trading of rare cards
May 2017: South Carolina-based designer Beeple (Mike Winkelmann) begins producing digital artworks titled "Everydays"
June 2017: New York-based Larva Labs (John Watkinson and Matt Hall) launches the Cryptopunks, 10,000 unique characters for sale on the Ethereum blockchain
August 2017: Ari Meilich and Esteban Ordano in Argentina launch the blockchain-based game Decentraland
October 2017: Vancouver-based Axiom Zen (mainly the team of Mack Flavelle, Dieter Shirley, Fabiano Soriani) launches CryptoKitties, a game that enables players to collect and breed virtual cats, on the Ethereum blockchain, illustrated by Guilherme Twardowski, aka Guile Gaspar
October 2017: Peter Weibel curates the exhibition "Open Codes" at the ZKM Center for Art and Media in Germany.
October 2017: Dada.nyc, a social network (founded in 2014 by New York-based artists Bea Ramos and Yehudit Mam) for artists to create collaborative digital art, unveils its first collection of NFTs "Creeps & Weirdos"
November 2017: Sarah Friend's Ethereum-based game "Clickmine" at the NEoN Digital Arts Festival in Scotland makes fun of clicking and mining by generating a hyperinflationary Ethereum token
November 2017: John Crain in New York founds SuperRare, a digital art market for NFTs on Ethereum
November 2017: Virginia-based Kevin Trinh and Matthew Russo launch Rare Art Labs, a platform for digital artists and art collectors
December 2017: CryptoKitties, the most used smart contract in the world, crashes Ethereum
December 2017: Alex Atallah's and Devin Finzer's OpenSea platform for NFT creation
January 2018: William Entriken, Dieter Shirley, Jacob Evans and Nastassia Sachs publish ERC-721, the standard for NFTs, inspired by Ethereum's ERC-20 token standard
January 2018: Tommy Nicholas and Rare Art Labs organize the first Rare Digital Art Festival in New York featuring Mack Flavelle of Crypto Kitties, Kevin Trinh is the founder of Rare Art Labs, Beatriz Ramos of Dada.nyc, Matt Hall of Cryptopunks, Shaban Shaame of Spells of Genesis, etc
February 2018: An anonymous person solves Marguerite de Courcelle's puzzle "Torched H34R7S" (2015), unlocking 5 bitcoins
April 2018: Blockchain game My Crypto Heroes by Doublejump.tokyo (Hironobu Ueno)
August 2018: Vietnamese studio Sky Mavis led by Trung Nguyen launches the NFT-based game Axie Infinity
September 2018: Simon Denny curates the exhibition "Proof of Work" by at the Schinkel Pavillon in Berlin
January 2019: Australian-based duo Chris Laurent and Rob Salha launches the NFT-based game Zed Run
February 2019: London-based curator Sascha Bailey launches the Blockchain Art Exchange on the Ethereum blockchain
July 2019: James Ferguson's and Robbie Ferguson's blockchain-based game Gods Unchained
September 2019: Roneil Rumburg and Forrest Browning in San Francisco launch the Ethereum-powered streamine platform Audius, basically a decentralized Spotify competitor
January 2020: Alexei Falin's and Alex Salnikov's Rarible, a decentralized exchange for NFTs
February 2020: Miami-based art collector Pablo Rodriguez-Fraile and investment banker Colborn Bell found the virtual art gallery Museum of CryptoArt
February 2020: San Francisco-based Conlan Rios launches an art platform for cryptoart, Async Art, on the Ethereum blockchain
July 2020: SuperRare launches a crypto art museum on Decentraland
July 2020: Jona Wilmsmann's and Fabian Emilius' AtomicHub for NFT creation
March 2021: A collage of Beeple's first 5,000 "everydays" sells for a record $69 million, the first NFT to be sold by a major auction house (Christie's)
March 2021: Sales of nonfungible tokens pass $2 billion in Q1 of 2021, more than 20 times the volume of the previous quarter
March 2021: Superchief (Edward Zipco & Bill Dunleavy) opens a brick-and-mortar NFT art gallery in New York City
April 2021: Qinwen Wang and Sun Bohan produce the world's first crypto art exhibition at the UCCA Center for Contemporary Art in Beijing, "Virtual Niche"
April 2021: Greg Solano and Wylie Aronow launch the Bored Ape Yacht Club
June 2021: Matthew Schapiro and Zachary Grochocinski open a brick-and-mortar NFT art gallery in Chicago, Imnotart
June 2021: The auction house Sotheby's opens a virtual gallery in Decentraland
June 2021: Linz-based Oo Landes-Kultur opens on Cryptovoxels the virtual exhibition "Proof of Art" on the history of digital art
July 2021: Alexander Kehaya's Holaplex for NFT creation
August 2021: Audius passes 5 million users and becomes one of the biggest consumer-centric decentralized applications ever
September 2021: Axie Infinity is the largest NFT project yet, having sold more than $2 billion worth of Ethereum NFTs
November 2021: Sinziana Velicescu opens a brick-and-mortar NFT gallery in Los Angeles, Vellum
November 2021: Craig Marshall's Objkt for NFT creation