Layer 1 in blockchain technology refers to the base or main blockchain network where all core operations take place. It is the foundational layer responsible for transaction processing, consensus, security, and data availability. In simple terms, Layer 1 is the blockchain itself, the system that records transactions, validates blocks, and maintains the shared ledger.

Popular examples of Layer 1 blockchains include Bitcoin and Ethereum. These networks operate independently and do not rely on another blockchain for security or settlement. Every transaction broadcast to the network is verified by nodes and added to the blockchain according to the protocol’s rules.

Layer 1 blockchains are designed to prioritize decentralization and security. They use consensus mechanisms such as Proof of Work or Proof of Stake to ensure that no single entity controls the network. This makes Layer 1 highly secure and resistant to censorship, but it can also limit transaction speed and increase fees during high network activity.

Another key role of Layer 1 is final settlement. Once a transaction is confirmed on Layer 1, it is considered final and irreversible. Layer 1 also supports native assets, validator incentives, and protocol-level governance.

While Layer 1 networks face scalability challenges, they remain essential. They provide the trust, security, and foundation upon which Layer 2 solutions and decentralised applications are built. Without Layer 1, the broader blockchain ecosystem cannot function reliably or securely.