Comments are statements that will not be executed by the interpreter, comments are used to mark annotations for other programmers or small descriptions of what your code does, thus making it easier for others to understand what your code does.
// This is a comment, it will be ignored by the interpreter var a = "this is a variable defined in a statement";
/*and ending with
*/, this method is used for multi-line comments:
/* This is a multi-line comment, it will be ignored by the interpreter */ var a = "this is a variable defined in a statement";
/* Mark me as a comment or I'll throw an error */