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What if Assets Were Physical Objects?

In Solidity, tokens are numbers in a mapping. In Move, they're resources that physically exist and move between accounts - like handing someone a dollar bill instead of updating two bank ledgers.

Let's implement a basic token transfer to see the paradigm shift:

contract Token {
    mapping(address => uint256) public balances;
    
    function transfer(address to, uint256 amount) public {
        require(balances[msg.sender] >= amount, "Insufficient balance");
        
        // Two ledger updates - sender and receiver
        balances[msg.sender] -= amount;
        balances[to] += amount;
    }
}
info

you're a bookkeeper:

  • Manually track balances in mappings
  • Ensure conservation (no creating/destroying value)
  • Guard against reentrancy attacks
  • Hope you updated all the right ledgers

Moving Physical Resources​

In Move you're handling physical objects that exist in one place at a time. When you transfer a token, you're not updating two balance entries - you're actually withdrawing a resource from one account and depositing it into another. The language guarantees that the resource cannot be duplicated, lost, or accessed from two places simultaneously.

module cedra::token {
    struct Coin has store { 
        value: u64 
    }
    
    public fun transfer(from: &signer, to: address, amount: u64) {
        // Coin physically leaves sender's account
        let coin = coin::withdraw(from, amount);
        
        // And moves to receiver's account
        // The coin can only exist in ONE place
        coin::deposit(to, coin);
    }
}

In Move, you're handling physical objects:

  • Resources can only exist in one place
  • Can't be copied or lost (unless explicitly allowed)
  • Reentrancy is impossible - you can't give away what you don't have
  • The language enforces conservation laws
Thinking in SolidityThinking in Move
"Update the mapping""Move the resource"
"Check then update""Take then give"
"Prevent reentrancy""Physics prevents it"
"Track all state changes""Resources track themselves"

You've seen how resources change the game and that's just the beginning. Move's design eliminates entire classes of vulnerabilities that plague Solidity. Ready to see what else makes Move a paradigm shift?

📖 Understanding the Differences​

→ Concepts: Move vs Solidity: Complete comparison of every major concept - accounts, storage, execution, type systems, security models, and more

🎯 Start Building​

→ Your First Token: Create a fungible asset in 15 minutes → Build an NFT: Launch your NFT collection → Counter App: Complete dApp with frontend

Quick Challenge: Can you implement a flash loan that's guaranteed to be repaid? Hint: In Move, it's 12 lines using "hot potatoes" 🥔 - Learn more in the Resource Types guide

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