Computability; Functions and Relations; The Basic Machine; Macros; Closure Properties; Definitions of Recursive Functions; Codes; Indices; Church's Thesis; Word Problems; Undecidable Theories; Relative Recursion; The Arithmetical Hierarchy; Recursively Enumerable Relations; Degrees; Evaluation of Degrees; Large RE Sets; Functions of Reals; The Analytical Hierarchy; The Projective Hierarchy