We review the concepts of C-infinity ring and C-infinity scheme. Then, we sketch a proof that the category of C-infinity rings, the opposite of the category of C-infinity rings, and the category of C-infinity schemes admit tangent structures in the sense of Rosický, Cockett, and Cruttwell. Lastly, we discuss Sikorski differential spaces and explain how the existing tangent bundle functor for Sikorski differential spaces compares to the aforementioned tangent structures.