# USDD Intro

USDD is an **over-collateralized decentralized stablecoin that** is issued by TRON DAO Reserve, who is also the custodian. USDD is minted by the whitelisted institutions of the TRON DAO Reserve (TDR) through burning TRX. Its value is backed by the over-collateralization of highly liquid crypto assets under the TDR, including BTC, USDT, USDC, and TRX. The circulation and use of USDD are free from the intervention of any centralized parties. Similar to BTC and ETH, USDD grants its holders full ownership, meaning that no organization or individual has access to freeze users’ USDD.

USDD is now circulated on several mainstream chains. For more details, please check: <https://usdd.io/#/>.

## **Decentralized**

The USDD protocol aims to provide the blockchain industry with the most stable, decentralized, tamper-proof, and freeze-free stablecoin system, a perpetual system independent from any centralized entity.

## **Over-Collateralized**

USDD is secured by the over-collateralization of multiple mainstream digital assets (e.g. TRX, BTC, and USDT). The total value of collateralized assets is significantly higher than that of USDD in circulation with the collateral ratio set at 120%, far exceeding the 120% required for DAI.

## **Chain-Agnostic**

USDD can now circulate on multiple mainstream networks. Users can transfer USDD across different networks via cross-chain bridges. Similar to TRC20-USDT, USDD caters to users' needs by offering a fast and affordable experience on TRON.


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