If you have spent any time in a wallet on Base, you have probably seen an NFT show up in your assets tab even if you never bought one on purpose. NFTs are one of the most talked about parts of crypto, but the mechanics behind them are simple once you separate the token standard from the hype. This article covers what an NFT actually is, how it works on Base, and what to check before you interact with one.
What NFT actually means
NFT stands for non fungible token. Fungible means interchangeable. One USDC is worth exactly the same as any other USDC, so USDC is fungible. An NFT is the opposite: each one has a unique identifier, so token number 42 in a collection is not interchangeable with token number 43, even if they belong to the same contract.
Technically, an NFT is just an entry in a smart contract that records who owns a specific token ID. The contract does not usually store the image or video itself. Instead it stores a link, called the metadata URI, that points to a file describing the NFT's name, image, and attributes. That file often lives on IPFS, a distributed storage network, rather than on a normal web server. This matters because if the linked file ever goes offline, the NFT itself still exists on chain, but the image may fail to load in your wallet or a marketplace.
The two standards you will actually run into
Almost every NFT on Base follows one of two token standards, both originally defined on Ethereum and reused on Base because Base is an EVM compatible network.
ERC-721 is the original NFT standard. Each token ID is unique and has exactly one owner at a time. Profile picture collections and most single edition art pieces use this standard.
ERC-1155 is a multi token standard. A single contract can manage many token types, and each type can have multiple copies, similar to a limited print run. This standard is common for gaming items, editions, and collections where the creator wants several people to own the same design.
Your wallet does not need to treat these differently for basic use. Both show up as an NFT with an image, a name, and a link back to the contract on a block explorer.
Why NFTs ended up on Base
Base is a Layer 2 network built on the OP Stack, which means it settles transactions back to Ethereum while keeping day to day fees much lower than Ethereum itself. Minting and trading NFTs on Ethereum mainnet can cost real money in gas fees alone, which pushed a lot of NFT activity toward lower cost networks. Base has become one of the more active networks for new NFT projects because of this fee difference combined with its direct tie to Ethereum's security model. Marketplaces including OpenSea support Base directly, and Zora, a creator focused NFT protocol, runs natively on Base with on chain royalty enforcement built into its contracts.
None of this changes how ownership works. An NFT on Base is secured by the same private key model as any token in your wallet. Whoever controls the wallet's private key controls the NFT.
How minting and buying actually work
Minting means calling a function on an NFT contract that creates a new token and assigns it to your address. This is a normal transaction, so it costs gas and requires your wallet's confirmation. Buying an existing NFT on a marketplace works similarly to a token swap: you approve the marketplace contract to interact with your funds or your NFT, then confirm the actual sale transaction. Always read what a transaction is asking you to sign. A prompt to "approve" a marketplace contract is different from a prompt to "transfer" an NFT, and confusing the two is how many NFT thefts happen.
What to check before you interact with an NFT
A few habits go a long way here, especially since NFT scams are common:
- Verify the contract address. Look up the collection on a block explorer and confirm the contract address matches what the official project or marketplace lists. Scammers sometimes deploy fake copies of popular collections.
- Be careful with unsolicited NFTs. If an NFT you never minted or bought suddenly appears in your wallet, do not interact with it. Some scam NFTs are designed so that clicking a link inside their metadata or trying to "claim a reward" tied to them prompts a malicious signature request.
- Check what you are approving. Marketplaces need permission to move your NFTs on your behalf, but that permission should be scoped to what you are actually doing. Review and periodically revoke approvals you no longer need.
- Understand that metadata can be off chain. If a project's image server or IPFS pin goes down, the NFT can look broken even though you still legitimately own it on chain.
The bottom line
An NFT is a unique entry on a smart contract, made possible by the ERC-721 or ERC-1155 standard, and owned by whoever holds the private key to the wallet it is assigned to. Base's low fees have made it a popular place for NFT projects, but the security fundamentals are unchanged from any other token: verify contracts, read what you sign, and treat unexpected NFTs in your wallet with the same suspicion you would give an unexpected email attachment.