Transferring tokenOwnerShip from a deployed contract!

:1234: Code to reproduce

:computer: Environment

Hi everyone, I have a question regarding nft marketplaces. For example if I mint a token on Opensea, then if I want to to go and list it on Mintable I can!! How is Mintable able to list the token on their site and it can interact with their smart contract such as buying, selling, or transferring ownership. even though this token lives in the Opensea smart contract? How do they add it to their ERC721 contract? Do they mint it all over again? Or there is no need to mint it again? are they able to interact with the Opensea contract?


That is why we have standardization. Mintable knowns how to interact with OpenSea contract ... and OpenSea knowns how to interact with Mintable contract ... and both know how to interact with all other ERC721/1155 that exist out there (Poap, ENS, ...)

Thank you so much for your reply!! I'm still not sure how they interact with the with a contract that has been deployed by someone else.? for example if I have a contract I'm developing can I be able to use opensea's smart contract in my own by just using the contract address or how would that work? My question to be specific how can I develop my contract to be able to use functions of another contract of the same standard that has been already deployed on the blockchain?

I think I just figured it out, correct me if I'm wring but by using the standard ERC interface??