Code
Values of type Code represent some functionality or calculation. Often is it passed as an argument into some scripting commands which will execute it straight away, or at some later time, e.g. call, addEventHandler or onMapSingleClick.
The text body that makes up Code are also scripting commands.
Code literals are represented by enclosing text into curly braces. { code.... } Any such code is precompiled by the script engine. Code values may also originate as a text, which can be converted to code using compile command.
Armed Assault formalised this 'convention' by creating a Code Type. In previous versions it was a prefered style to write such strings in curled braces, but it was also possible to write them in quotation marks (exactly like Strings). ArmA commands that are marked as requiring Code must be presented with curled braces. Resistance / Cold War crisis commands using a Code style paramater should also used curled brace as a good writing style that was adopted very early on by most mission makers.