A string representing a JavaScript expression, statement, or sequence of statements. The
expression can include variables and properties of existing objects.
Don't use any quotes, or put all terms inside one set of quotes. eval(x + "3 * 4") returns 92
by concatenating 2 to 3, then multiplying 23 by 4! eval("4 * 3" + x) returns 128 by
concatenating 3 to 2, then mutiplying 4 by 32!