1. What are blockchains?

Wednesday 6th April 2022

Imagine a database that is provably immutable / unchangeable and almost impossible to hack. That’s a blockchain.

Imagine a world without computer databases. There would be no Amazon, no ATMs, no Internet banking, no Gmail, no Whatsapp, no LinkedIn, no YouTube!

Almost everything that makes the digital world so powerful and useful depends upon computer databases. Now imagine a database that is provably immutable / unchangeable and almost impossible to hack.

That’s a blockchain.

A blockchain is typically a bunch of computers (nodes) connected to each other. All of these computers contain the same information (e.g. a ledger of transactions). To “hack” this information, you will need to “hack” most of these computers at the same time. And that’s a pretty tough thing to do!

Blockchain technology started off with 1 usecase - a cryptocurrency called Bitcoin. But today Blockchain has become an integral part of our lives with use cases like:
1. Asset Tokenization
2. Crypto Assets
3. Decentralized Autonomous Organizations (DAOs)
4. Decentralized Finance (DeFi)
5. Metaverse & Gaming
6. Non-Fungible Tokens (NFTs)
7. Web3
...and even storage of COVID vaccine passports by the Government!

There are many blockchains in the world. The Bitcoin Blockchain is the first and oldest one. It records all transactions of the bitcoin cryptocurrency. Anyone can run a node of this blockchain. All you need is a computer with enough storage space and a strong Internet connection.

Some of the most popular blockchains are:
1. Algorand
2. Avalanche
3. Binance Smart Chain
4. Cardano
5. Celo
6. Ethereum (Mainnet)
7. Fantom
8. Flow
9. Polkadot
10. Polygon
11. Solana
12. Stacks
13. Stellar
14. Terra
15. Tezos
16. Waves