Given regular cardinal $\kappa>\omega,$ we can define the canonical functions $f_\alpha: \kappa\to \kappa,$ for $\alpha<\kappa^+.$
Some of their properties are presented in Chapter 22 of the book "Problems and Theorems in Classical Set Theory" by Péter Komjáth and Vilmos Totik.
(A) I am looking for more references and additional properties of these functions.
(B) I also want to know what are the main applications of these functions, and how they can be used in proving theorems (in particular $ZFC$ results).