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A "Bridge"–Blockchain Bridge is a mechanism or tool that describes the minting and burning processes to establish a stable supply of tokens between two heterogeneous blockchains. This is done by locking a particular token in one blockchain network, and you mint the equivalent of the locked token on the second blockchain that was bridged to the former. An example of such a cross-chain bridge is the Harmony Bridge –a.k.a. Horizon Bridge. Harmony Bridge was attacked, and altcoins to the tune of $100 million were swapped for ETH and siphoned.