Yearn Vaults are a feature within the Yearn.finance ecosystem, which is a decentralized platform for automated investing that enables users to maximize returns from their funds provided to various DeFi protocols. This feature offers automated investment strategies designed to optimize returns while minimizing fees and risks. Vaults operate by allowing users to deposit their cryptocurrencies, and then smart contracts invest these funds into different DeFi projects and strategies with the goal of achieving the highest possible profit.
As for the LUSD yVault, this would be a specific product within the Yearn Vaults focused on the LUSD cryptocurrency. LUSD is a stablecoin typically pegged to the value of the US dollar and is often used in the DeFi space for its stability and reduced volatility. Therefore, the LUSD yVault would likely implement strategies optimized for LUSD, aiming to provide LUSD holders with passive income through automated investments and leveraging various DeFi options and tools.