When MAXScript parses an expression on the command line that contains names, it looks for a variable with this name in the current scope and then outer scopes, out to the global scope. If it doesn't find a variable with this name, it creates one in the current scope.
For example the name "IntervalArray" in the following statement is treated as a variable initialization:
myArray = IntervalArray 10.0 26.0 4Depending of the context of the variable (e.g. the variable is followed by a list of arguments, or it is followed by ()) then MAXScript may evaluates the variable as a function call. If the value is evaluated as a function call but is not a function type, then a runtime error is thrown.