The term „interoperable blockchain“ belongs in the categories of blockchain, digital transformation, and finance. A blockchain is like a digital ledger that many users maintain together and that stores all transactions in a tamper-proof way. In the early days, blockchains could mostly only work individually. An „interoperable blockchain“ makes it possible for different blockchains to communicate with each other and exchange data or values.
Imagine blockchains were like languages: one speaks only English, the other only German. Without a common translation, they don't understand each other. Interoperable blockchains act like a translator. For instance, they help you transfer digital coins or information from one blockchain to another, without the need for cumbersome exchanges.
A vivid example: Peter owns Bitcoins, which are stored on the Bitcoin blockchain, but he wants to put them into a programme that runs on the Ethereum blockchain. Thanks to an interoperable blockchain, Peter can easily move his Bitcoins into the desired programme without having to sell his Bitcoins first and buy new digital currencies.
Interoperable blockchains are therefore an important step towards better connecting and making digital worlds more flexible.
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