A subroutine is a reusable block of script that can be called from other places in the QlikView script by using the CALL statement. This block is formed using the SUB and END SUB control statements. Subroutines can contain parameters so that processing can be done in a flexible manner. As the QlikView script is processed in sequential order, the subroutine has to be defined before it can be called. Therefore, it is advisable to create subroutines as early as possible in the script. When executing the script, everything between the SUB and END SUB control statements is ignored by QlikView. The subroutine is only run when it is called via the CALL statement.