7.3 Function Scope: The Call Object
In addition to local variables and parameters, the call object defines one special property named arguments. This property refers to another special object known as the Arguments object, which is discussed in the next section. Because the arguments property is a property of the call object, it has exactly the same status as local variables and function parameters. For this reason, the identifier arguments should be considered a reserved word and should not be used as a variable or parameter name.