Understanding JavaScript primitive values ​​and composite values

JavaScript data types can be divided into two types: primitive types and reference types. Primitive types are also called basic types or simple types. The basic data types of JavaScript include Undefined, Null, Boolean, Number, and String. Reference types are also called complex types, which are Object in Javascript. Correspondingly, their values ​​are also called primitive values ​​and complex values ​​respectively

Compare with Java data types:

Primitive values: the basic data types Undefined, Null, Boolean, Number and String

Composite Value: Can be composed of many different types of javascript objects