The book is intended for computer science students, programmers and professionals who have already got acquainted with the basic courses and background on discrete mathematics. It may be used as a textbook for graduate course on theoretical computer science.
The book introduces a reader to the conceptual framework for thinking about computations with the objects. The several areas of theoretical computer science are covered, including the following: type free and typed A-calculus and combinatory logic with applications, evaluation of expressions, computations in a category. The topics, covered in the book accumulated much experience in teaching these subjects in graduate computer science courses.
А rich set of examples and exercises, including solutions, has been prepared to stimulate the self studying and to make easier the job of instructor.