
Dewmal Handapangoda
Software Architect | AI Specialist | Senior Lecturer at iCET

Blockchain technology has revolutionized how we think about digital transactions, ownership, and decentralized systems. From Bitcoin’s inception to today’s Web3 ecosystem, this comprehensive guide will walk you through everything you need to know.
A Brief History of Blockchain and Why It Was Needed
Before Blockchain
Digital records relied on central authorities (banks, governments) to stop fraud. There was no way to create decentralized, trustless digital money. Every digital transaction required a middleman, creating single points of failure and limiting global accessibility.
The Breakthrough (2008)
Satoshi Nakamoto’s Bitcoin white paper introduced blockchain: a secure, decentralized ledger that solved the double-spending problem without requiring trusted intermediaries. This breakthrough laid the foundation for an entirely new digital economy.
Why Was Blockchain Needed?
- Remove single points of failure
- Enable tamper-proof records
- Allow peer-to-peer money without banks
Beyond Money
- Run programs (smart contracts)
- Create tokens and NFTs
- Enable decentralized applications (dApps)
- Power Web3 economies
What is Blockchain?

Definition
A special database that stores data in linked blocks. Think of it as a digital ledger that’s duplicated across thousands of computers worldwide, making it virtually impossible to hack or manipulate.