4.3.19
Number value
primitive value corresponding to a double-precision 64-bit binary format IEEE 754 value
NOTE A Number value is a member of the Number type and is a direct representation of a number.
4.3.20
Number type
set of all possible Number values including the special ―Not-a-Number‖ (NaN) values, positive infinity, and negative infinity
4.3.21
Number object
member of the Object type that is an instance of the standard built-in Number constructor
NOTE A Number object is created by using the Number constructor in a new expression, supplying a Number value as an argument. The resulting object has an internal property whose value is the Number value. A Number object can be coerced to a Number value by calling the Number constructor as a function (15.7.1).
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