Ripple USD (RLUSD) is a digital asset that operates on the Ripple payment protocol, designed for fast and low-cost cross-border transactions. It serves as a bridge currency in the Ripple network, facilitating the exchange of different fiat currencies. RLUSD can be used for transferring value on the Ripple platform, but its value is not directly tied to any specific fiat currency. It is traded on various cryptocurrency exchanges and is popular among institutions and individuals looking for efficient international payment solutions.