rBTC.b stands for restaked BTC.b. Users deposit BTC.b and receive rBTC.b at a 1:1 ratio. Yield Yak then acts as a Curator on Suzaku Network's marketplace for Avalanche L1s looking for crypto-economic security for their network. Yield Yak delegates BTC.b collateral to operators in exchange for rewards, which are compounded back into the BTC.b, increasing rBTC.b's value over time. In this way users can gain access to these rewards while supporting the growth of the Avalanche network.