- subroutines：blocks of code
- Define：define a subroutines means writing the code
- call：calling a subroutines means writing the code
- procedure:is a subroutine that carries out actions
- Function:is a subroutine that returns (make) a new value
- Subroutine:a.Each subroutine is given a name . The code in the subroutine is typically stored outside of main program.
- Define and Call:a.A subroutine is defined in one part of the program . It is called in a different part of the programme .
- Why use subroutine? a.programs are shorter , quicker to write and have less repetition.