A bridge is a protocol that lets you move tokens and data between two different blockchains.
Different blockchains cannot talk to each other natively. Bridges let you use an asset from one chain on another, such as moving Ethereum to a layer 2.
Most bridges lock tokens on the source chain and mint an equivalent token on the destination chain. The reverse burns the token and unlocks the original.
Bridges hold large amounts of locked assets and have been a frequent target of hacks, some of the largest in crypto history.
Use well-established bridges, move only what you need, and be aware that bridging carries additional risk.
Bridges connect the crypto ecosystem, but they are complex and have been a weak point, so use them with care.