L1 vs L2: the layered blockchain landscape

Different layers, different jobs

Once Ethereum got popular, it ran into a problem. The network could only process so many transactions per second, and during busy periods fees got expensive — sometimes a single swap cost more than the trade was worth. Two paths opened up to fix this. The first path was build a different Layer 1 — a brand-new blockchain with its own validators, designed to be faster from the start. Solana, Avalanche, Sui, and Aptos are examples. They each have their own consensus, their own block space, and their own native token. They are not built on top of anything. They compete directly.

The second path was build on top of Ethereum. That is what a Layer 2 is. Arbitrum, Optimism, Base, and zkSync are Layer 2s. They process transactions cheaply and quickly off the main chain, then periodically post a compressed summary back to Ethereum so that the base chain still has the final say on what happened. You get most of Ethereum's security guarantees with a fraction of the cost. The trade-off is added complexity — bridges between layers, slightly different liquidity in each ecosystem, and the need to trust that the L2's mechanism is working correctly.

As a trader, this layered map matters for two reasons. First, when capital rotates inside crypto, it does not always rotate evenly. Sometimes Solana attracts volume while Ethereum sits quiet. Sometimes Base or Arbitrum captures retail flow while alt L1s lag. Watching where activity is concentrated tells you where narratives are forming. Second, each ecosystem has its own native token. SOL is the asset behind Solana. ARB and OP are tokens tied to their respective L2s. Their charts react to chain-specific news, not just to BTC sentiment.

Recap: L1s are standalone chains. L2s are scaling layers built on top of an L1, usually Ethereum. Each has its own token, and capital does not always rotate between them evenly. Knowing where activity is helps you read which corner of the alt market is leading.