About NFT

About NFT's

If cryptocurrencies are like digital coins, an NFT is similar to a limited-edition medal or special coin produced in small quantities.

While some NFTs are expensive collector’s items, they also serve practical purposes. For example, an NFT can act as a receipt to prove that you’ve made a payment or completed an action. It can also function as a key to unlock special online content.

NFTs are much better than Passwords!!

Using an NFT as a key is far more secure than a password. A password can be copied and shared, allowing multiple people to use it. In contrast, an NFT is unique and can only be owned by one person at a time.

It behaves like a key in the physical world !

Let's use Polygonscan to scan the address used in these tutorials: 0xF0E4227a9872360D3C99A514B3fA2FE321437312 Since this address has been publicly exposed in this wiki and other places, bots have found it and sent trash, scams, advertising, etc to it.

Find the NFT with Polygonscan

Use PolygonScan to scan this Polygon address: 0xF0E4227a9872360D3C99A514B3fA2FE321437312

Click on token holdings, and scroll down to find the NFTKEY

Warning: You may find other SPAM NFT's and potential Scams!

Click on the NFTKEY tab (Marked by an arrow) to open the NFT contract page, filtered by Token Holder

As you can see, NFTs are very disappointing!! There is no nice picture, text or anything other than the TOKEN CONTRACT (see the orange arrow above)

So What is an NFT Then?

NFTs are pretty much like any other token, but they exist in very small quantities. They are created by a smart contract and they contain no information themselves. All that matters is who owns them. Once deployed, the NFT token can be "owned" by any address in the same blockchain.

The NFT KEY in this example was created in OpenSea, a popular platform for creating NFT's quickly without coding knowledge. The Smart Contract that deployed our NFT KEY was created, and thus is owned, by OpenSea. A limitation if you want to have the full control over your NFTs.

The 0x06467... TOKEN CONTRACT address was deployed by OpenSea and it is called a "collection" of NFTs and the NFTKEY is the Token ID 1 in this collection.

There are 1001 NFTKEYs "minted" by this contract.

The individual NFTs contain no particular information, but the smart contract that deployed them contains "Meta Data" which typically is an IPFS address. (see next section)

In that address the information related to the NFT is stored. This includes text, pictures, and some other file types.

In the next section we will check out the metadata in our NFT contract. Just let's talk about IPFS

IPFS : Interplanetary File System

IPFS stands for InterPlanetary File System. It’s like a decentralized internet storage.

Instead of storing files on one server (like Google Drive or Dropbox), IPFS stores files across many computers around the world.

Key Points:

• Decentralized Storage: No single owner; files are shared across a network.

• Content-Based Addressing: Files are found by their unique fingerprint (called a CID, or Content Identifier), not by a location or URL.

• Permanent & Immutable: Once a file is added, it doesn’t change. If you change the file, it gets a new CID.

Often used in blockchain projects to store things like NFT images or metadata, because blockchains can't store large files directly.

Example:

Traditional Web:

 _https://example.com/image.png  → Points to a server.

IPFS:

 ipfs://bafybeibwzif...  → Points to "what" the file is, not "where".

Anyone who has the CID can access the file, as long as at least one computer in the network is sharing it.

If you're familiar with torrents, it's a bit like that, but designed for the web, permanent storage, and decentralized apps (dApps).

NFT MetaData

We can get the MetaData directly from the smart contract, which we will do in the next section to show that we can interact directly with the smart contract.

But if you own an NFT you can use OpenSea to see the metadata associated with it.

You would go to this address (substitute the 0xF0E4... address with your own). In the link below you can't scan the 0xF0E... address, you need to connect the wallet in order to see the NFT's

https://opensea.io/0xF0E4227a9872360D3C99A514B3fA2FE321437312

OpenSea is like a "wallet" for your NFTs and can retrieve the MetaData of the smart contract directly for you. Here you can see that the 0xFOE address has an NFT KEY:

If you don't see the NFT you may have to update the OpenSea version, or force it to re-load or re-connect to your wallet.

Click on "Zodiac Key" to get to the NFT page, notice that it is identified by the blockchain (matic) the TOKEN CONTRACT, and the Token ID = 1

Access Metadata with OpenSea

Now click in the "About" Tab to access the NFT metadata:

In the upper right corner of the OpenSea page, where you see your Polygon address, you can select: "Connect Wallet"

When you connect your wallet you have more options available, like the "send" button here:

You can use OpenSea as an "online wallet" for your NFTs and you can send them to any other Polygon address. If all you want to know is how to use the NFTs this is enough, but...

What if OpenSeas website disappears? How do we check the NFT metadata?, how do we transfer the NFT from one address to another?

For this we have to: Interact directly with the TOKEN CONTRACT

You don't need all this information to continue with your Zealy quests. But it is very important if you want to understand deeply the NFT technology.