ABSTRACT
This chapter provides an example to emphasize that functions of first Baire class play a significant role in various topics of real analysis. It considers real-valued functions of two variables and briefly discusses their descriptive structure from the view-point of descriptive properties of the corresponding partial functions of one variable. The consideration is restricted to real-valued functions defined on the topological product of two metric spaces. The chapter also includes exercise problems related to the functions of first Baire class.
