A genesis block is very similar to your first commit when you view your commit logs using git log.
It is the very first block in a blockchain [↗].
Transactions and data are stored on blockchains as blocks, and the chain part refers to how these blocks are linked to each other (the hash from the previous transaction becomes a part of a future one).
A genesis block plays a crucial role in blockchains. Being the first record, it not only defines the initial state of the blockchain but also sets a precedent for all future blocks.
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