Why does the same transfer cost so much less on Layer 2?
Layer 2 is a scaling network built on top of the Ethereum mainnet. It executes transactions off-chain and then submits the results to the mainnet.
Before withdrawing assets from Layer 2 to the mainnet, check whether you’re using the official bridge or a third-party cross-chain bridge—the arrival time and fees differ.
$ARB and $OP are the governance tokens for Arbitrum and Optimism, respectively. Currently, 0.1846.
If anything is unclear, ask me in the comments.

#ARB

NFA—do your own research.