Aave began as ETHLend in 2017 — a peer-to-peer lending platform matching individual borrowers and lenders — and pivoted in 2020 to become Aave (Finnish for "ghost"), adopting a pool-based lending model that became the dominant paradigm for DeFi lending. The model change was transformative: rather than matching individual lenders to individual borrowers (requiring both sides to agree on rates and durations), Aave pools all supplier deposits of each asset and all borrowers draw from the pool at algorithmically determined interest rates. Interest rates adjust automatically based on utilisation: low utilisation means cheap borrowing rates (to attract borrowers); high utilisation means expensive borrowing rates (to attract more suppliers and deter over-borrowing). This mechanism creates stable, self-regulating interest rate markets with no counterparty matching required. Aave V3 is now deployed across 12+ networks including Ethereum, Arbitrum, Optimism, Polygon, Avalanche, Base, and Gnosis, with $15B+ TVL across all deployments.
How Borrowing Works: Collateral and Health Factor
Aave is an over-collateralised lending protocol: to borrow $100 of USDC, you must first supply more than $100 worth of collateral (ETH, wBTC, or other accepted assets). The collateral ratio required depends on the asset's risk parameters — ETH typically allows 80% LTV (you can borrow up to $80 of USDC for $100 of ETH collateral). Your "health factor" is a summary of your position's safety: a health factor above 1.0 means you're safe; below 1.0 triggers liquidation (a third party can repay part of your loan and claim your collateral at a discount). Liquidation risk increases when: your collateral's price falls, your borrowed asset's price rises (for non-stablecoin borrows), or accumulated interest increases your debt. Managing health factor — and adding collateral before it drops too low — is the core risk management task for Aave borrowers. Use cases: borrowing stablecoins against ETH/BTC collateral to access liquidity without selling the collateral (useful when you believe price appreciation is likely); leveraged long positions (supply ETH → borrow USDC → buy more ETH); shorting assets (supply stablecoins → borrow the asset you want to short → sell it).
Flash Loans: The Uncollateralised DeFi Primitive
Flash loans are Aave's most technically innovative feature and a concept unique to blockchain: uncollateralised loans of any size, available to any user, that must be borrowed and repaid within a single transaction. The atomicity of blockchain transactions is the collateral: if the borrower can't repay the full amount plus fee by the end of the transaction, the entire transaction reverts — as if the loan never happened. Flash loans have no credit checks, no collateral, no counterparty risk, and no limit (you can borrow Aave's entire liquidity if you can return it in one tx). Use cases: arbitrage (borrow $10M USDC, buy asset on DEX A, sell on DEX B where price is higher, repay loan, keep profit — all in one transaction); collateral swaps (replace your loan's collateral asset in one step without needing to repay first); liquidations (borrow the funds needed to liquidate an undercollateralised position, collect the liquidation bonus, repay the flash loan, keep the profit). Flash loans are primarily used by sophisticated DeFi developers and arbitrage bots; they also feature prominently in DeFi exploits — several "flash loan attacks" have used the primitive to manipulate prices within a single block, draining vulnerable protocols.
GHO: Aave's Native Stablecoin
GHO (launched July 2023) is Aave's native overcollateralised stablecoin, minted by depositing collateral on Aave and borrowing GHO against it — similar to MakerDAO's DAI model. GHO's key difference: instead of a stability fee paid to a protocol, GHO borrow interest accrues to the Aave DAO treasury, making GHO a revenue source for AAVE governance. AAVE token stakers in the Safety Module get a 30% discount on GHO borrow rates, creating an incentive to stake AAVE. GHO is not pegged via an AMM (unlike Curve's 3pool for DAI/USDT/USDC) but maintained through arbitrage: if GHO trades below $1, borrowers can repay their GHO debt for less than $1 face value; if above $1, it's profitable to mint new GHO and sell it. GHO's peg has been imperfect during periods of market stress — maintaining strong peg stability is an ongoing priority for Aave governance.
AAVE Token: Safety Module and Governance
AAVE's investment case is among the strongest of DeFi governance tokens because it has genuine staking utility. AAVE holders can stake in the Safety Module — a backstop that can be partially slashed (up to 30%) to cover shortfall events (situations where a major liquidation cascade leaves the protocol with bad debt). In exchange, Safety Module stakers earn approximately 5–8% APY in AAVE rewards. The staking mechanism creates demand for AAVE from risk-tolerant holders willing to backstop the protocol in exchange for yield. AAVE also earns protocol revenue from borrower interest rates (the "collector contract" accumulates protocol fees), and the governance treasury can allocate these revenues to AAVE buybacks, liquidity incentives, or development grants. As DeFi matures and lending volumes grow, Aave's structural position as the dominant lending protocol positions it to benefit more from ecosystem growth than many other DeFi tokens.
Aave V3 and GHO Stablecoin
Aave V3 introduced efficiency mode (e-Mode) allowing borrowers to access higher LTV ratios when borrowing assets correlated with their collateral — for example, borrowing stETH against ETH collateral at up to 93% LTV because their prices are closely correlated. This capital efficiency improvement significantly reduces over-collateralization requirements for users rotating between correlated assets in yield strategies. Portal (V3's cross-chain feature) allows seamless asset movement between Aave deployments on different chains, improving capital utilization across the multi-chain Aave ecosystem spanning Ethereum, Arbitrum, Optimism, Polygon, and more.
GHO — Aave's native overcollateralized stablecoin — allows stkAAVE holders to mint GHO at a discounted rate, creating direct utility for AAVE stakers beyond safety module staking rewards. Facilitators (whitelisted entities who can issue GHO through alternative mechanisms like flash-minting) expand GHO's use cases beyond standard CDP minting. The AAVE safety module (stkAAVE) requires AAVE stakers to act as the protocol's last-resort capital — in a shortfall event, up to 30% of staked AAVE can be slashed to cover protocol losses, making staking a security commitment rather than pure yield farming. AAVE trades on Coinbase, Binance, Kraken, and Bybit. Use our crypto tools for AAVE analysis and our DennTech blog for DeFi lending updates.