They are required. Argument names Argument names, including return arguments, are always shown in lowercase characters. Arguments must be listed in the same order in your program as they appear in the format. Spaces One or more spaces are used between the entry point name and the first argument, and between each argument. They are not required.
Brackets surround optional arguments.
The brackets are not required. Commas Commas are required between arguments. Commas that appear inside brackets are optional and appear only when the optional argument appears. For widget creation routines, a list of the resources and their corresponding types. Return Value A description of the possible values that can be returned by the routine.