A named common is a global, common, BASIC variable space used to store variables and arrays in the area identified by ID. Named common space is initialized only at logon and released at logoff.
Named common space is common for all levels of the same process (that is, level pushes, executes, file-time bridges and indexes, and so on).
Variables and/or arrays can be used for communication between programs and subroutines providing interprogram communication.
common /ID/ variable|array{,variable|array...}
common /expenses/ emp,date,category