Data classification of JS

> Raw Data types
>
>>1, simple data segment
>>2, stored value (stack)
>
> Reference Data types
>
>>1, with multiple values constituting an object
>>2, stored address (heap)

6 Types of raw data type or basic data type

1,null (empty, not present)
2,undefined (1, Declaration unassigned, 2, function has no return value)
3,number (Numbers, decimals, and integers)
4,boolean (boolean value, True,false)
5,string (string, single or double-cited)
The 6,ES6 symbol primitive data type produces a unique value through the symbol (), which can be used to transmit the parameter symbol (' DD '), the String class, which does not affect its value, as a property value

-Reference data type or complex data type
----
The 1,object object object is an unordered set of properties, where the "properties" can be basic values, objects, or functions
2,array Array
3,function function
4,object is the parent of all reference types

Detection data type

typeof

Data classification of JS