Flash Loan
An uncollateralized blockchain loan that must be borrowed and repaid within the same atomic transaction.
Explain Like I'm 12
An uncollateralized blockchain loan that must be borrowed and repaid within the same atomic transaction.
Why It Matters
DeFi concepts explain blockchain-based markets, lending, trading, liquidity, and financial automation.
How It Works
The user triggers a smart contract function that requests a flash loan. The contract sends the funds to the user's smart contract, which then performs operations like arbitrage. At the end of the script, the contract checks if the borrowed amount plus fees are returned. If not, the transaction fails.
Real-World Example
Aave Flash Loans, used frequently for arbitrage and liquidations.
Advantages
- Zero collateral required
- High capital efficiency
- Enables advanced strategies
Limitations
- Requires advanced coding skills
- Susceptible to flash loan attacks
- High gas costs
Common Misconceptions
- People think flash loans are for everyone, not just programmers.
- Many believe they can run away with the borrowed funds.
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Related Terms
DEX
A Decentralized Exchange (DEX) is a peer-to-peer marketplace where users trade cryptocurrencies without an intermediary or central authority. Unlike centralized exchanges (CEXs) that hold user funds and process trades internally, DEXs utilize smart contracts to execute trades directly between wallets. This setup ensures that users maintain custody of their assets until the moment of the trade, promoting censorship resistance and financial sovereignty.
Liquidity Pool
A liquidity pool is a crowdsourced collection of digital assets locked in a smart contract to facilitate decentralized trading and lending. Unlike traditional order books where buyers and sellers must be matched, liquidity pools use Automated Market Makers (AMMs) to enable permissionless exchange. By pooling funds, the protocol ensures that there is always a counterparty available for trades, maintaining market depth even for less popular tokens and reducing reliance on centralized intermediaries.
Smart Contract
A smart contract is a self-executing program stored on a blockchain that automatically runs when predetermined conditions are met. These contracts eliminate the need for intermediaries by encoding terms directly into lines of code, ensuring that the agreement is enforced exactly as written without human interference. Because they reside on an immutable ledger, the execution results are verifiable, transparent, and impossible to tamper with once deployed.
Smart Contract
A self-executing program stored on a blockchain that automatically enforces and executes the terms of an agreement when predetermined conditions are met. Smart contracts are deterministic, immutable once deployed, and form the backbone of decentralized applications.
Stablecoin
A stablecoin is a type of cryptocurrency designed to maintain a stable value by pegging its price to an external asset, such as the U.S. Dollar, gold, or a basket of other assets. Unlike volatile cryptocurrencies like Bitcoin or Ethereum, stablecoins provide a reliable store of value and medium of exchange within the DeFi ecosystem. They are maintained through various mechanisms, including fiat collateralization, algorithmic adjustments, or over-collateralization with other crypto assets.
Stablecoin
A cryptocurrency designed to maintain a stable value by pegging to an external asset, typically a fiat currency like the US dollar. Stablecoins provide price stability for DeFi applications, trading pairs, and as a bridge between fiat and crypto ecosystems.