If you use a keyword as a variable or function name, you will probably be greeted with an error message like this: “Identifier
in a sense, words that are reserved for future use as keywords. Because of this, reserved words cannot be used as variable or function names. The complete list of reserved words in ECMA-262 Edition
3 is as follows:
If you use a reserved word as a variable or function name, more than likely you will not receive an error...until a future browser implements one of them. Then the word will be considered a keyword, and you will get a keyword error.