Layer 1, in the context of blockchain and cryptocurrency, refers to the underlying foundational protocol of a blockchain network. It is the primary layer where the main blockchain operates, handling tasks such as transaction validation and consensus mechanisms. Layer 1 solutions are critical for the security and integrity of the entire blockchain system. Examples include Bitcoin and Ethereum, where the base layer supports the core functionalities of their respective networks. As the foundation of decentralized systems, Layer 1 protocols set the stage for the development of additional layers and scaling solutions in the blockchain ecosystem.