Blockchain is just like a database or distributed ledger technology that is used to keep the records of transactions.
Then, you will think how it's different from current technology. Then, the answer is that everything in blockchain is encrypted and every transaction record is visible by everyone but no one knows which transaction is yours as it is visible in encrypted format but not in actual format.
Let, me explain with an example:-
Suppose, you make a transaction of bitcoin either you send or receive some bitcoins.
Then, for this transaction a hash value is generated that gets executed on blockchain network in encrypted format.
Like this- f01d54x73ha91dfa62c5ca4b277d9ad146e
Which holds all your transaction details but no one knows whom this belongs to & even no can can manipulate or alter any details with this transaction because it is stored on thousands of computers & even at one computer if someone manipulates data then other thousands computers holding the transaction will automatically corrects the data. As, each node or computers are connected with the network & regularly syncs the data.
So, no one can hack any transactions on blockchain.
What transformation can blockchain introduce in our current technology?
As, we can clearly notice from above definitions of blockchain that hacking any transactions or manipulation with transaction details is not possible.
So, in our banking system blockchain can make it hack-free means 360° protection over banking transactions.
But, not only this but it can also be implemented in various sectors like transfer of contracts, data, storing data etc.
Hope, you all got some basics introduction about blockchain in simple words.
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