What is frax backed by?

Could you elaborate on the underlying assets that Frax is backed by? Understanding the collateralization of this cryptocurrency is crucial for investors to assess its stability and potential value. Is it backed by a traditional fiat currency reserve? Or perhaps a mix of different digital assets? Clarifying the composition of its backing is key to determining its credibility and market positioning within the broader crypto ecosystem. Could you please provide a detailed breakdown of Frax's collateralization?