Definition
The genesis block is the starting block of a blockchain, assigned height zero. Unlike later blocks, it does not extend an earlier block within that chain. Bitcoin software identifies a specific genesis block as part of its network configuration, establishing the initial reference from which subsequent block relationships are traced. Different networks, including testing environments, can have different genesis blocks even when they use related software. The term describes a technical starting point, not a guarantee that a project is decentralized or trustworthy. A new cryptocurrency can create its own genesis block while choosing very different rules for issuance, permissions, and validation. When examining network data, the genesis reference helps distinguish one chain from another. It also illustrates why a copied codebase does not automatically share Bitcoin's transaction history, accumulated proof of work, or native BTC balances.
Source references
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