Layer 1 Blockchain Meaning

The foundational layer of a decentralized network. This is the base protocol that handles the core functions of security, consensus, and data availability.

Bitcoin, Ethereum, Solana, and Avalanche are all examples of Layer 1 (L1) blockchains. An L1 is responsible for its own security, usually through Proof of Work or Proof of Stake.

All transactions are settled directly on this ledger, which acts as the "ultimate source of truth." However, L1s often face a "scalability trilemma," where they struggle to process high volumes of transactions quickly and cheaply without sacrificing decentralization. Because every transaction on an L1 must be verified by a global network of nodes, the fees (gas) can become very high during periods of congestion.

This has led to the development of "Layer 2" solutions, which sit on top of the L1 to handle the "heavy lifting" of transactions while still relying on the L1 for final security and settlement.