DeFiLetter: D

What is Decentralized Finance (DeFi)?

Definitive Definition

Decentralized Finance (DeFi) is an open financial ecosystem of smart contracts, decentralized applications (dApps), and protocols built on public blockchains that replicate traditional banking services—such as lending, borrowing, trading, and asset management—without intermediaries.

In-Depth Architectural & Economic Analysis

DeFi replaces centralized financial intermediaries (banks, brokerages, clearinghouses) with self-executing software programs called smart contracts. Users interact directly with decentralized liquidity pools and lending markets using non-custodial cryptographic wallets.

Core Characteristics & Mechanism

  • Non-custodial: Users maintain full private key control of their capital.
  • Permissionless: Anyone with an internet connection can participate.
  • Composability: DeFi protocols interoperate seamlessly like "money legos".
  • Transparent: All transactions, collateral ratios, and code are publicly auditable.
Practical Application Scenario:

A trader deposits $10,000 of ETH into Aave as collateral to instantly borrow $6,000 of USDC without credit checks, loan officers, or paperwork.