Functions of bounded variation are most important in many fields of mathe¬matics. This thesis investigates spaces of functions of bounded variation with one variable of various types, compares them to other classical function spaces and reveals natural “habitats” of BV-functions. New and almost comprehensive results concerning mapping properties like surjectivity and injectivity, several kinds of continuity and compactness of both linear and nonlinear operators bet¬ween such spaces are given. A new theory about different types of convergence of sequences of such operators is presented in full detail and applied to a new proof for the continuity of the composition operator in the classical BV-space. The abstract results serve as ingredients to solve Hammerstein and Volterra in¬tegral equations using fixed point theory. Many criteria guaranteeing the exis¬tence and uniqueness of solutions in BV-type spaces are given and later applied to solve boundary and initial value problems in a nonclassical setting. A big emphasis is put on a clear and detailed discussion. Many pictures and syn¬optic tables help to visualize and summarize the most important ideas. Over 160 examples and counterexamples illustrate the many abstract results and how de¬licate some of them are.