NFT stands for Non-Fungible Token, which is a type of digital asset that represents ownership or proof of authenticity of a unique item or piece of content. Unlike cryptocurrencies such as Bitcoin or Ethereum, which are fungible and can be exchanged on a one-to-one basis, NFTs are unique and cannot be exchanged on a like-for-like basis.

NFTs are typically built on blockchain technology, most commonly using the Ethereum blockchain, although other blockchains like Binance Smart Chain and Flow are also used for NFTs. The blockchain provides a decentralized and transparent ledger that verifies and records ownership and transaction history of NFTs.

NFTs can represent a wide range of digital or physical items, including artwork, music, videos, virtual real estate, collectibles, and more. They have gained significant popularity in the art world, allowing artists to sell their digital creations directly to collectors and retain control over their work. NFTs provide a way to prove the originality, rarity, and ownership of digital assets in a secure and verifiable manner.

One of the key features of NFTs is that they can contain "smart contracts," which are self-executing contracts with the terms of the agreement directly written into the code. These smart contracts can automate various aspects of ownership, such as royalties, licensing rights, or other conditions that artists or creators may want to enforce.

The sale and purchase of NFTs usually take place on specialized online marketplaces called NFT platforms. These platforms facilitate the creation, minting, buying, and selling of NFTs, often using cryptocurrency as the primary medium of exchange.

It's important to note that while NFTs have gained a lot of attention and value, there are also debates and criticisms surrounding their environmental impact due to the energy consumption associated with blockchain technology. Additionally, as with any digital asset, the value of an NFT is subjective and can fluctuate based on market demand.

Please keep in mind that my knowledge cutoff is September 2021, so there may have been new developments and trends in the NFT space since then.