Introduction To Blockchain


When you receive any goods from someone, what made you determine its originality? How can you trust, if the goods you received are not tampered with? One of the ways is to keep track of all the transactions related to these goods in a ledger system. From the beginning of the human era, people recorded all the transactions of their day to day life. People used ledgers and wrote down the transactions.

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Problem statement

As we evolved into the digital age, most of our transactions were recorded in the digital format. Recording this transaction is not easy but it's also complex. Mainly it is complex because it’s misinterpreted easily and it also becomes a target for vulnerabilities.

Example 1

Importing mobile phones

Suppose you order mobile phones from other countries. The journey of those mobile phone involves legal, regulatory, manufacturing and custom practices, until it reaches your repository. Here, many people are  involved including agents, dealers, banks and lawyers etc. Here, the chances of tampering with your order (mobile and its information’s/parts) is high because it has to go through multiple channels. Thus, there should be a transparent ledger, which holds all the transactions, which is initiated from the supplier to the consumer. This is where Blockchain comes into the picture. This is an open ledger, where everyone involved in the process is having transparent transactions. Blockchain offers secure and synchronized transactions.

Example 2

Suppose, person ‘A’ wants to transfer money to person ‘B’. This is typically done, using a third party (trusted party). Trusted party will identify the target party and then transfer the money after taking some money as a commission. This is also slow to process.


Blockchain will try to transfer the money without any third party trusted entity. Second, it is faster and immediate. Third, it is cheaper.


Why it is cool?

Blockchain is cool because all the information will sit in personal nodes in a network. It not only makes it decentralized but it also makes it distributed. Each transaction that occurrs will be placed in a block and it’s connected to the other blocks. Fingerprint of the block is added to the next block, which makes a stable strong irreversible chain. This is not owned by any central person. Everyone owns it and helps in its running. This uses Cryptography, so that it cannot be tampered with.

Thus, if we consider back to the above mobile example, all the transactions are transparent to the entire stakeholders. No new entry can be added without the consent of the stakeholders involved. This means no one person can alter the bock chain. It's secure and trusted! 

Examples of industry where Blockchain can be used
  • Government
  • Healthcare
  • Insurance
  • Retail
  • Finanance 
Helpful Resources
  • Programming Language Solidity:
  • YouTube session:
  • Project Bletchley:
  • Ethereum Doc:
  • Framework
  • White Paper
Blogs and Videos