All terms
A network that processes transactions off chain but settles to a layer 1.
A layer 2 executes transactions in its own environment, then posts the results and enough data back to the layer 1 for anyone to verify or challenge them.
The result is much cheaper and faster transactions while still inheriting the security of the base chain, provided the design is sound and the escape hatch works.
Base and Arbitrum both settle to Ethereum. Fees are a fraction of a cent because thousands of transactions share one settlement cost.
That a layer 2 inherits all of the base chain's security automatically. It inherits settlement, and it adds its own assumptions about sequencers, upgrade keys and withdrawal delays. Most of the real risk on a layer 2 lives in those extra pieces.
Common questions
Are funds on a layer 2 as safe as on layer 1?
How long does it take to withdraw from a layer 2?
Where this comes up on the site
The guides that actually use this word, rather than a list of everything we have written.
Where to go next
More technology terms
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