A COBOL program can call a subprogram that is linked into the same executable module as the caller (static linking) or that is provided in a DLL (dynamic linking). COBOL for Windows also provides for runtime resolution of a target subprogram from a DLL.
If you link a target program statically, it is part of the executable module of the caller and is loaded with the caller. If you link dynamically or resolve a call at run time, the target program is provided in a library and is loaded either when the caller is loaded or when the target program is called.
Either dynamic or static linking of subprograms is done for COBOL CALL literal. Runtime resolution is always done for COBOL CALL identifier and is done for CALL literal when the DYNAM option is in effect.
related concepts
CALL identifier and CALL literal
Static linking and dynamic linking
related references
DYNAM
CALL statement
(COBOL for Windows Language Reference)