JavaScript 2.0-The Complete Reference, Second ... - freecodingtutorial

Table A-7: Primitive JavaScript Data Types
Type Description Values Literal Syntax
or true/false
values and
conditionals.
null Has only one
value. Indicates
the absence of
data, for
example, placed
in unspecified
function
argument.
number Includes both
integer and
floating-point
types. 64-bit
IEEE 754
representation.
Integer ops
usually carried
out using only 32
bits.
string Zero or more
Unicode (Latin-1
prior to Netscape
6/IE4)
characters.
undefined Has only one
value and
indicates that
data has not yet
been assigned.
For example,
undefined is the
result of reading
a non-existent
object property.
null null
Magnitudes as
large as
1.797610 308
and as small as
2.225010 -308 .
Integers
considered to
have a range of
2 31 –1 to –2 31 for
computational
purposes.
Any sequence of
zero or more
characters.
Decimal values
(including exponent),
hexadecimal, octal
Single- or doublequote
delimited
undefined undefined
(IE5.5+/NS6+/ECMA3)
as a property of
Global. Previously not
available
JavaScript/ECMAScript defines a select number of numeric constants, which are detailed in
Table A-8. The Math object, discussed in Chapter 7 and Appendix B, also includes a variety of
useful values such as Math.PI.
Table A-8: Useful Numeric Constants
Numeric Constant Description
Infinity Infinity (property of Global)
NaN Not a number (property of Global)
Number.NEGATIVE_INFINITY Negative infinity
Number.POSITIVE_INFINITY Positive infinity