What is Blockchain?

Blockchain is like a digital ledger shared by many computers. When someone wants to add a record, it becomes a block in the chain. Other computers verify the block's validity before adding it.

Each block has a unique code linking it to the previous block.

Tampering with a block changes the code and gets noticed.

It's secure, transparent, and doesn't need a central authority. Crypto currencies like Bitcoin use blockchain, but it has other uses too.

Imagine you have a notebook that you share with a group of friends. Whenever someone wants to make an entry or a record, they write it down in the notebook and show it to everyone. Everyone in the group has a copy of the notebook, and they can see all the entries.

Now, let's apply this concept to blockchain. Instead of a physical notebook, imagine a digital ledger or a database that is shared among many computers or "nodes." Whenever someone wants to make a transaction or record something, it gets added to the ledger as a "block" of information.

Before a block can be added to the ledger, it needs to be verified by the other computers in the network. They check if the transaction is valid and if it follows the rules of the blockchain system.

If everything checks out, the block is added to the ledger, and it cannot be changed or deleted.

Each block in the blockchain contains a unique code called a "hash" that links it to the previous block, creating a chain of blocks. This is why it's called a blockchain.

So, if someone tries to tamper with a block in the middle of the chain, it will change the hash, and the other computers will notice that something is wrong.

This decentralized and transparent nature of blockchain makes it secure and reliable. It eliminates the need for a central authority like a bank or government to control transactions.

Instead, the power is distributed among the network of computers, ensuring trust and immutability.

Blockchain technology has gained popularity for its application in crypto currencies like Bitcoin, but it can be used for various other purposes like supply chain management, voting systems, smart contracts, and more.