|String||Variable-length string that can be up to approximately 2 billion characters in length in the Unicode character set .|
Writing the whole number constant:
Decimal numbers are written normally, for example 0, 3, -10003.
Hexadecimal numbers start with 0x, for example 0xff, 0xCAE91F2.
Writing the floating point number constant: Real number is written normally with decimal point, for example 3.14. It can also be written in exponencial form: the letter e is written after the real number, followed by a plus/minus sign and a whole number exponent, for example 7.12e+32, 2.458268e-12.
|Boolean|| Logical value: |
true (numeric value is "nonzero", mostly -1) or
false (numeric value is 0)
|Object||General, undefined object.|
|null||Flag that value intentionally contains no valid data.|