What Is a Bridge Between Networks

A bridge is a service or protocol that moves tokens from one blockchain network to another: from Ethereum to BNB Chain, for example, or from Polygon to Arbitrum.

Why you would need one

Different blockchains cannot talk to each other directly. Ethereum has no visibility into what happens on Solana, and vice versa. A bridge solves that problem by letting you move an asset from one chain to another.

How it works, roughly

You send a token to the bridge on the source network. The bridge locks or burns that amount and issues an equivalent token on the destination network. The result: the same asset, now on a different chain.

What to pay attention to

Bridges vary widely in how they are built and how much trust they require. Some are controlled by a team holding keys. Others operate through smart contracts and oracles. The industry has seen several large bridge exploits: a vulnerability in a smart contract or trusted vault led to users losing funds. Use mature, well-established solutions.

Wrapped tokens

After crossing a bridge you often receive a wrapped version of the token, not the native asset. Wrapped Bitcoin instead of native BTC, or wrapped ETH on another network. They trade close to the original by price, but technically they are different contracts. That matters when sending to a wallet or exchange that expects a specific version.

When a bridge makes sense, and when it does not

If you want to swap ETH for SOL, using a cross-chain swap service is usually simpler: one step, no manual interaction with a bridge.