This book features the interplay of two main branches of mathematics: topology and real analysis. The material of the book is largely contained in the research publications of the authors and their students from the past 50 years. Parts of analysis are touched upon in a unique way, for example, Lebesgue measurability, Baire classes of functions, differentiability, $C^n$ and $C^{infty}$ functions, the Blumberg theorem, bounded variation in the sense of Cesari, and various theorems on Fourier series and generalized bounded variation of a function. Features: Contains new results and complete proofs of some known results for the first time. Demonstrates the wide applicability of certain basic notions and techniques in measure theory and set-theoretic topology. Gives unified treatments of large bodies of research found in the literature.