blockchain
A distributed digital ledger that records transactions across many computers so that records cannot be altered retroactively.
Example
“Bitcoin uses blockchain technology to ensure that every transaction is permanently and publicly recorded.”
Memory Tip
Literally a CHAIN of BLOCKS — each block of transactions is chained to the previous one.
Why It Matters
Understanding blockchain matters because it underpins cryptocurrencies and digital assets that are increasingly used for investments and transactions. Many people are considering adding crypto to their portfolios, so knowing how blockchain technology secures and records these transactions helps you make informed financial decisions about whether to participate in this market.
Common Misconception
Many people believe that blockchain transactions are completely anonymous and untraceable, but in reality most blockchains create a permanent public record of all transactions tied to wallet addresses. While names may not appear directly, sophisticated analysis can often link wallet addresses to real individuals, making privacy far less absolute than commonly assumed.
In Practice
Imagine you purchase 0.5 Bitcoin for $20,000 and transfer it to your digital wallet. That transaction is recorded on the Bitcoin blockchain across thousands of computers worldwide, creating a permanent timestamped record showing your wallet sent 0.5 BTC to another address. Even if you try to dispute the transaction later, the distributed ledger means no single entity can alter or delete this record, making the transaction effectively irreversible.
Etymology
Compound of 'block' (a group of transactions) and 'chain' (linked together in sequence).
Common Misspellings
Buy Bitcoin & crypto with low fees
Related Terms
More in cryptocurrency
Other cryptocurrency terms you should know
See Also
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