How Blockchain Actually Works (Plain English)
A blockchain is a special type of database that is shared across a network of computers. It records information in a way that makes it nearly impossible to hack, change, or cheat.
The Simple Definition
Each page = a block. Once written, nobody can erase or rewrite it.
How Data Is Stored
Instead of saving all data on a single server, blockchain distributes it to the computers in the network — called nodes.
- Each block stores verified transactions
- Each block is cryptographically linked to the previous one
- Changing one block would break the entire chain
Who Keeps The Blockchain Honest?
Independent computers called validators verify every transaction that happens. They use consensus mechanisms to agree on what’s true.
| Method | Used By |
|---|---|
| Proof of Work (PoW) | Bitcoin |
| Proof of Stake (PoS) | Ethereum |
What Happens During a Transaction?
1️⃣ You request a transaction
2️⃣ Validators confirm it’s real
3️⃣ The block is added to the chain
4️⃣ It becomes permanent history 🔐
What Makes Blockchain Special?
- No single authority controls it
- Public and transparent records
- Hard to hack, easy to verify
- Trust built into the system
Real-World Blockchain Uses
- Cryptocurrency — sending money globally
- NFTs — digital art & collectibles
- DeFi — banking without banks
- Supply chain tracking for products
