In plain English
What Decentralized exchange means
A DEX commonly lets a user connect a non-custodial wallet and authorize a smart contract to swap tokens. Some DEXs use liquidity pools and an automated pricing formula; others use on-chain or hybrid order books. The protocol may be governed, developed, or supported by identifiable parties, but trade execution is designed to follow deployed code and blockchain rules.
Why it matters
A DEX can allow direct wallet-based trading, yet it introduces distinct technical and transaction risks. Users must select the correct token and network, understand fees and price effects, and assess smart-contract and token risks. A blockchain transaction is generally irreversible once confirmed, and a protocol’s decentralized design does not itself establish regulatory status or customer protections.
Example
Mateo connects a wallet holding 1,000 USDC to a DEX and requests a swap for ETH. The interface shows an estimated output of 0.30 ETH, a network fee, and a maximum permitted price movement. Mateo signs the transaction; the smart contract executes the swap if its conditions are met. A mistaken token contract address could result in buying an unintended token instead.
Quick answers
Common questions
Does a decentralized exchange always use an order book?+
No. Many DEXs use automated market makers, where liquidity pools and a mathematical formula determine quoted swap prices. Other designs use order books or combine off-chain order handling with on-chain settlement.
Do I keep custody when using a DEX?+
Typically, you keep control of your wallet credentials, but a swap requires you to authorize a smart-contract transaction. That approval can permit defined actions by the contract, so its scope and the protocol’s legitimacy should be understood before signing.
Sources