Understanding blockchain could be confusing. Let’s understand it through an analogy first.
You may have seen or have been to many weddings, everyone in a wedding is like a conscious blockchain. In a wedding, everyone writes in their mental register that a certain man got married to a certain woman now if anyone claims that this woman is my wife (or she is not married), then everyone (present at the wedding) will reject this claim.
If a member of a study group misrepresents a topic in front of other members, the rest of the members will reject it because the topic written in this member's mental register does not match the rest of the members.
That's how blockchain works in real.
I hope you've understood blockchain through an analogies, let's look into the actual definition of a blockchain.
Blockchain is a peer to peer (a network with equal permission and responsibilities), decentralized (every node/computer makes their decision), distributed (a system where parts of a system exist in different physical locations) public ledger between various nodes/computers. It keeps a complete, durable and unchanging record of the transactions that take place. The transaction is timed that is, with the transaction, the time of its occurrence is also written in such environment where there is a lack of trust.
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