Lesson 3: Smart Contracts Introduction

Key Learning Objectives:

• Understand what smart contracts are and how they work
• Learn about Ethereum and the EVM (Ethereum Virtual Machine)
• Explore real-world smart contract applications
• Understand the basics of Solidity programming language

What are Smart Contracts?

Smart contracts are self-executing programs that run on blockchain networks. They automatically execute predefined actions when certain conditions are met, without requiring intermediaries.

Ethereum: The Smart Contract Platform

Ethereum, created by Vitalik Buterin, introduced the concept of programmable blockchain. It allows developers to create decentralized applications (dApps) using smart contracts.

The Ethereum Virtual Machine (EVM)

The EVM is the runtime environment for smart contracts on Ethereum. It ensures that all contracts execute in a secure, isolated environment with consistent behavior across all nodes.

Solidity: The Smart Contract Language

Solidity is the primary programming language for Ethereum smart contracts. It's designed to be similar to JavaScript and C++, making it accessible to many developers.

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract SimpleStorage {
    uint256 private storedData;
    
    function set(uint256 x) public {
        storedData = x;
    }
    
    function get() public view returns (uint256) {
        return storedData;
    }
}

Real-World Applications

Smart contracts enable a wide range of applications beyond simple transactions: