How is WBTC backed?

Could you elaborate on the backing mechanism of WBTC? I'm particularly interested in understanding how it maintains its pegged value to Bitcoin. Does it involve any form of collateralization or does it rely solely on market forces? Also, how does the process of minting and redeeming WBTC work? I'm trying to get a clear picture of its underlying structure and how it functions within the broader cryptocurrency ecosystem. Thank you for your insights.