Blockchain: It’s one of the upcoming futuristic technology that you will be going to see in the next couple of years. So, In this article, we’re going to have a brief discussion about Blockchain Technology and how It works.

What is Blockchain Technology?

Blockchain is a list of blocks which connected through peer to peer network. Where you can consider each block as a database. But It’s not a centralized database. Because blockchain is a distributed system, where each block has copies of transactions or ledger(distributed).

Firstly, Blockchain was used by Satoshi Nakamoto to develop bitcoin cryptocurrency in 2008. Currently, most of the people think that blockchain and bitcoin is the same thing, but it’s not. Bitcoin is just a part of entire blockchain technology e.g email is part of the Internet.

Concerns Related to BlockChain

Because we all know that blockchain is a decentralized system, therefore, you might have concerns related to this technology. Let’s clear the all confusion related to it.


You might be thinking that is it secure or not. Because of decentralization, anyone can temper the data within it. But let me tell you that It’s fully secured. Because In the blockchain, each and every block linked by using cryptography. Where each block contains three different things data, a hash key(Generated by hashing algorithm), the previous hash key.

So, If anyone will change the data then they will have to change the data of the previous block too. Because each alteration(even miner) of the data will change the hash key totally. Which means then “the previous hash key of the current block will not match with the current hash key of the previous block”. So If anyone would change the data then everyone will know it.


Now let’s talk about trust. how you can trust on this technology. Because it’s a decentralized network, therefore there is no single organization that controls it. Suppose, In the bank, if you’re sending money to someone then there is a bank in between, which ensures the transaction. But in blockchain, there is no central database then what if someone will deny that you have sent any money to him. That’s where ledger comes in the picture.

In Blockchain, each block or node maintains records into the ledger(distributed ledger). Every block maintains its own ledger, which is immutable(not changeable). But even if someone will change something in their ledger or any transaction will happen. then ledger of each block will be updated, because hash key of each block will be updated.

How Blockchain Works(GUIDE)

Now let’s talk about how blockchain technology works behind the scene. Because now at least we have an idea about What is blockchain. As we discussed that before In blockchain, we have a list of the block that strung together. Where each block maintains its own ledger.

I’ll try to simplify this process as much easy as I can.

In each block, we have three different section(A,B,C): (A)previous hash key, (B)data(anything that), (C) current hash key.

Each block stores data or anything which can be virtually stored e.g info, data, transactions, documents, etc. then each block gets their hash key, which has generated using hashing algorithm. Where current hash key of current block will be the previous hash key of next block. So, what happens if any transaction will happen then current hash key of previous block becomes previous hash key of new block.

Here, we have concept called hashing, In hashing, we have different types of algorithms that we perform on specific input(data) to generate a hash key for that data. There are different algorithms in hashing like MD5, SHA 256, SHA 512, etc.

Example: Let’s assume, we have a message as input data. Message = “My Name is PK Karn”. Then we will perform SHA 256 hashing algorithm on our this message input. As a result, it will generate hash key for that message. suppose, our generated hash key is “BS29SHJ3HJ3J3HEHJEF4H0S04300J“. In this block, our data is message and hash key is “BS29SHJ3HJ3J3HEHJEF4H0S04300J

Now each block has a different hash key like above. And hash key of each block becomes the previous hash key of the next block or node. Therefore, if someone will try to change the data then the hashing will be again performed and it will generate the different hash key.

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I hope you now you all have an idea about blockchain technology. And the important part how it works behind the scene.

Thank’s to read…

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