There are so many Blockchain networks, and each of these new blockchains has its native token. Consequently, it became incredibly difficult for these blockchains to interact seamlessly with each other.

Seeing that these native tokens from different Blockchains can not be used as the same token, nor can a token of a particular blockchain be used on another blockchain. This is where a Blockchain bridge comes in.

Take an example from the real world. You can’t use the Kenya currency KES in America, nor use the Canada CAD in Singapore. You’ll need the help of an exchange service to convert the currency you have to that of the country you are visiting.

Blockchain bridges are used to move tokens across different blockchains. Let’s say you have MATIC(Polygon’s native token) and you want to interact on Ethereum, ordinarily, it’s not possible, because you would need ETH(Ethereum’s native token) to enable you to interact with Ethereum blockchain.

All you have to do is to connect your wallet to a bridge e.g. Polygon Portal (formerly called Polygon POS Bridge). Thereafter input the amount of token you want to bridge and your destination blockchain(e.g Ethereum). What happens is that the bridge would “lock” your MATIC, and “mint” a wrapped version of MATIC (wMATIC) which you will receive in your wallet address, and can then use to interact on the Ethereum blockchain.

With this, the bridge allows your interaction on a blockchain with a token that is not its native asset. Hence, enabling interoperability between blockchains

What is the difference between a Bridge and a Swap?

A bridge is different from a swap.

With swap, you convert a token to the native token of a blockchain and use it within the ecosystem of that blockchain only.
In essence, if you swap your ETH for MATIC, you can only use your MATIC within the Polygon blockchain.

With a bridge, you mint your ETH to wETH and can use it to interact with another blockchain.

A bridge aids the transfer of tokens across different blockchains, a concept known as a cross-chain bridge.

Types of Blockchain Bridges.

Blockchain bridges are either centralized(cex) or decentralized(dex).

Using a centralized bridge requires that you trust the authenticity and integrity of the exchange service to safeguard and manage your assets.

A decentralized bridge is trustless, as its security and operations are controlled by smart contracts.

However, there are risks associated with using any type of bridge, both security concerns and other factors.

Do your due diligence.

Some examples of Blockchain bridges are: