🔍 What is Blockchain?
A blockchain is a decentralized, distributed ledger technology that records transactions across many computers in such a way that the registered transactions cannot be altered retroactively.
Key Features
- Decentralization
- Immutability
- Transparency
How It Works
- Transactions are verified by network participants
- Valid transactions are grouped into blocks
- Blocks are linked through cryptographic hashing
- Chain grows continuously in a decentralized manner
📦 Smart Contract Example
pragma solidity ^0.8.0;
contract SimpleStorage {
uint storedData;
function set(uint x) public {
storedData = x;
}
function get() public view returns (uint) {
return storedData;
}
}
This basic example shows a contract that stores and retrieves data from the blockchain using Solidity.
🔑 Key Blockchain Concepts
Chaining
Blocks are linked together using cryptographic hashes to ensure data integrity and historical traceability.
Cryptography
Public-key cryptography enables secure peer-to-peer transactions without intermediaries.
Consensus
Network participants agree on the state of the ledger using algorithms like Proof of Work or Proof of Stake.
🛠 Getting Started
1. Set up Environment
npm install -g truffle
npm init -y
npm install web3@1.0.0
2. Write Contract
// Sample contract
contract MyContract {
function store(uint x) public {
// Implementation
}
}