Blockchains are largely self-contained: Bitcoin has no awareness of Ethereum, and a token on one chain cannot simply appear on another by itself. A bridge is the connector that works around this. In a common design, you lock an asset on the source chain and the bridge issues, or mints, a matching representation on the destination chain; reverse the process and the original is unlocked again. This is how people move value onto a layer 2, for instance, or use one chain's asset inside another chain's applications.
Bridges unlock a great deal of flexibility, but they come with a clear warning that deserves stating plainly. They have been among the most heavily exploited pieces of crypto infrastructure, with several of the largest hacks on record targeting bridges, precisely because they concentrate a lot of locked value in one place and are technically complex. When you use a bridge, you are trusting its specific security model on top of the two underlying chains, not just the chains themselves.
For that reason, bridging is best done deliberately: understand what actually backs the wrapped asset you receive, favour well-established and audited bridges over obscure ones, and move a small test amount first before committing anything meaningful. The convenience is real, but so is the well-documented risk, and treating a bridge casually has cost users dearly in the past.
Key takeaways
- A cross-chain bridge moves assets or data between otherwise-separate blockchains, often by locking on one side and minting on the other.
- Bridges make assets usable across networks, including moving funds onto layer 2s.
- They are a frequent target of major hacks, so bridging carries real, well-documented security risk.
Cross-Chain Bridge — questions fréquentes
Why are bridges seen as risky?
Because they lock up large amounts of value and are technically complex, they make attractive targets, and several of crypto's biggest hacks have struck bridges. Using one means trusting its particular security design in addition to the two chains it connects.
What is a wrapped token?
It is a stand-in asset a bridge issues on one chain to represent a coin locked on another, such as a wrapped version of Bitcoin used on Ethereum. Its value depends on the original staying safely locked and redeemable at all times.
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