What are layers and bridges for?
Course · Web3 · 4 min
What?01 / 08
Layers and bridges
Stacked networks accelerate transactions; bridges move value between them.
Four minutes to separate speed, security and liquidity before changing chains.
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What?02 / 08
The base layer
A layer-one blockchain produces blocks, runs consensus and stores final state.
It balances security, decentralisation and capacity.
Scarce space can make transactions slow or expensive.
What?03 / 08
Layer two bundles
A layer two executes or bundles many operations away from the main layer.
It then publishes a proof or compressed batch to layer one.
It gains speed and lower costs while inheriting part — not always all — of the base security.
Why?04 / 08
Different trade-offs
Each system chooses its proof mechanism, withdrawal delay and operators.
A sequencer may order transactions while layer one settles the final result.
Two networks using the same wallet do not necessarily share the same security.
What?05 / 08
A bridge changes ledgers
A bridge does not teleport an asset: it coordinates two separate ledgers.
Often the asset is locked on one side and a representation is created on the other.
On return, the representation is destroyed and the original asset released.
Why?06 / 08
Why bridges break
A bridge must prove an event really occurred on the other network.
Compromised keys, too few validators or a verification bug can create unbacked assets.
Liquidity can also disappear, leaving a valid asset that is hard to use.
How?07 / 08
How to change networks
Destination — confirm the intended network in the wallet
Asset — verify the official representation address
Cost — keep native coins on both sides
Finality — wait for the stated delay before acting again
How?08 / 08
Follow the full path
A layer two is an execution environment; a bridge is a passage between environments.
Before moving value, identify who validates, where it is locked and how it returns.
The cheapest route is not always the one requiring the least trust.
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