This book is aimed at students of the technological direction of the 3rd grade of the Day General High School and the 4th grade of the Evening General High School.

It includes methodology, solved and unsolved exercises. Specifically, the topics covered in the book are as follows:
- Function call
- Procedure call
- Display of the execution time stack
- Writing a function
- Writing a procedure
- Writing a subroutine, without specifying whether it is a function or a procedure in the statement
- Converting a function to a procedure and modifying the main program that calls it
- Converting a procedure to a function and modifying the main program that calls it
- Replacing a program that has subroutines with an equivalent program that has no subroutines
- Creating a program using subroutines
- Solved and unsolved exercises
- Appendix with the solutions to all unsolved exercises.