Compiler directives give you options to control the actions of the Compiler. They allow you to enable language features, choose run-time behavior, choose compile-time options, create debugging information, control the format of data files, optimize the object code, and choose SQL options.
The compiler directives provided by the standard are described in the topic Compiler Directives.
The syntax of the directives and a description of each directive provided by this implementation are given in your COBOL system documentation.