Non-fungible tokens are dominating headlines, yet even many advanced investors are not familiar with the new investable asset class.

Fungible Vs. Non-Fungible: NFTs simply refer to a unique digital item that people can buy and sell with each other. Some of the more common NFTs in 2021 include collectibles and digital art. 

Taking a step back, it is important to talk about what exactly constitutes a fungible asset. Strictly speaking, a fungible asset or item is something that can easily be replaced with another identical item.

Bitcoin (Crypto: BTC) is one example of a fungible asset. If you have one bitcoin and sell it today, another bitcoin can be bought back the next day.

Alternatively, replacing one bitcoin with two half bitcoins would satisfy the conditions of being a fungible asset.

It won't be the same bitcoin you previously owned, but it will be identical in every shape and form.

Now, some fungible assets can also be considered non-fungible, such as a book. If you own a first edition copy of a book that gets destroyed in a fire, replacing it with an identical later copy is not a true replacement.

Related Link: How to Buy NFTs

The NFTs Investors Are Talking About: It wasn't previously possible for someone to own a limited edition e-book or another form of digital creation.

But the advancement of blockchain technology over the years has certainly changed the game and created a new industry.

For the first time ever, someone can create a digital book or piece of art and sell that one unique creation to one individual.

The blockchain provides a certificate of authenticity of sorts to prove the rightful ownership of a collectible item, like a digital painting.

NFTs can sell for as little as one penny and into the tens of millions of dollars. Items like trading cards, collectibles, domain names, art and much more can be bought on NFT platforms like OpenSea or CryptoRank.

A crypto-asset investor that goes by the pseudonym "Metakovan" bought a unique NFT artwork called "Everydays: the First 5000 Days" for just shy of $70 million.

Public Company Exposure: Here is a summary of a few names that investors have tied to the space or are rumored to be expanding into NFTs.

Takung Art Co Ltd (NYSE:TKAT) is a Hong Kong-based provider of an online trading platform for art collectors and investors to acquire fractional ownership in Asian and other fine art. Shares of Takung Art are up more than 330% since the start of 2021.

Oriental Culture Holding Ltd (NASDAQ:OCG) is an online provider of collectibles and artwork e-commerce services. The company's platform brings together collectors, artists, art dealers and owners to access an art trading market. Shares of Oriental Culture are higher by 37% since the start of 2021 but were down more than 30% on Tuesday.

ZK International Group Co Ltd (NASDAQ:ZKIN) is a China-based designer, engineer, manufacturer, and supplier of patented high-performance stainless steel and carbon steel pipe products.

On Monday, the company said its subsidiary xSigma Corporation is designing an NFT marketplace based on Ethereum (Crypto: ETH) and Polkadot platforms. Shares of ZK International are up more than 175% since the start of 2021.

Currencyworks Inc (OTC:CWRK) is a financial technology blockchain company that designs platforms for digital currencies, assets and security tokens. On March 12, the company said its existing NFT platform will expand to include Bitcoin and Ethereum as payment methods. Shares of Currencyworks are higher by nearly 250% since the start of 2021.