Worldcoin is the official project of the CEO (Sam Alman) of OpenAI (ChatGPT) and is essentially a decentralized (in theory), private and secure digital identity/passport system (which does not reveal personal data) stored on your smartphone. It is based on AI and has already been labeled as "creepy" and "despotic". In any case, in mid-July the 2 million registrations were already exceeded.

USE CASES
1) Voting in the DAO and quadratic voting
2) Unique identity on chain
3) Distribution of airdrops without the ability to create multiaccounts and sybil attacks
4) Protection against bots
5) Reputation system
6) CAPTCHA replacement to prevent DoS attacks

HOW DOES IT WORK?
How does the identity verification process work? You have to download WorldApp (a kind of wallet) and then look for the closest orb to your city via this website: WorldCoin (Find Orb)
The orb is closed source (this may cause some concern). What will the orb do? It will scan your retina and biometric data creating a hash (associated with your identity). What the system keeps is precisely this hash and not your personal data (this should guarantee some security). You will also receive a pair of keys to handle the wallet. The basic idea is precisely to verify that the person is human and not a bot, create a digital identity and then sign transactions with this hash providing a "proof of personhood".

This system would fight sybil attacks and multiaccounts because it would no longer be possible to create an infinity of accounts: the orb would understand if that retina has already been registered or not. It is a zero-knowledge proof because the systems you interact with would see a unique hash, even if they don't know your personal data. Creating this identity and using it on-chain pays in WorldCoin (WLD). The max supply is 10 billion and it is a Governance token which theoretically should be very decentralized because it will be given to all those who register with an orb and who use their dapp. This token uses Ethereum mainnet and its layer2 Optimism. You can also become an operator, by becoming an orb and thus earning tokens. You earn their token for every person who registers using your orb.

ANY PROBLEMS
The technology behind WorldCoin is very interesting because it facilitates interactions with the web3 and you are also paid to use it. However you should also consider any issues, before using it. One of the biggest problems is certainly the registry that is formed with all the scans of the irises. In theory, someone with a photo of your iris could check if you already have a WorldID and if you don't have one, create it using your identity (hash). Another problem is that orbs would have to be spread in all major cities of every nation, otherwise the mass diffusion of this tool would become impossible (it would not make sense to travel 300 km to create an identity). 
Through AI it is also possible to create fake 3D people by deceiving Orb software, obtaining the identity for a person who does not actually exist. Your phone could also be hacked and then attackers could exploit your identity. These are just some of the security problems for a system of this type that still remains interesting, even if it needs improvement. Revolutionary ideas need time to perfect!

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