Blockchain, Private blockchain and Distributed ledger

Firstly, blockchains are generally public, meaning that anyone can view transaction histories and can participate in their operations by becoming a node. They are, as cryptocurrency parlance puts it, “permissionless.”

By contrast, a distributed ledger generally doesn't enable any or most of these public features. It restricts who can use and access it ; permissioned , and it also restricts who can operate as a node. And in many cases, governance decisions are left to a single centralized company or body.And it isn't a time-stamped chain of blocks that results from cryptographic consensus, it often just amounts to a fairly conventional database that just happens to be shared among a select group of participants

As a conclusion, private blockchains, which technically are not blockchains but a better database management system. Nevertheless, it does have productivity gains whereas public blockchains like Bitcoin and Ethereum change the way we think and use money and computation which is open, neutral, censorship resistant and borderless. And distributed ledgers are simply permissioned databases.

Depending on where you sit on the Bitcoin vs. blockchain spectrum, some qualify Bitcoin-style blockchains as largely superior to and more innovative than their distributed ledger counterparts while others qualify DLT as more useful for everyday commercial purposes.

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