I am not able to understand exactly what is difference between primitive and non primitive data types in JavaScript even it is declared using same name i.e var.
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7Primitive have value, non-primitives have reference, this is the main differenceTushar– Tushar2015-10-22 05:14:40 +00:00Commented Oct 22, 2015 at 5:14
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Also, primitives are not initially instantiated as objects, whereas non-primitives are (I think this is the reason for value vs. reference as mentioned above).Informagician– Informagician2015-10-22 05:28:52 +00:00Commented Oct 22, 2015 at 5:28
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Types don't have anything to do with variables in JS, they are not "declared". They only belong to the values.Bergi– Bergi2015-10-22 06:14:30 +00:00Commented Oct 22, 2015 at 6:14
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2Possible duplicate of What is the main difference between primitive type and wrapper class?phuclv– phuclv2015-10-22 06:38:40 +00:00Commented Oct 22, 2015 at 6:38
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7 Answers
Data Types (JavaScript):
Primary Data Types
The primary (primitive) data types are:
String, Number, Boolean
Composite Data Types
The composite (reference) data types are:
Object, Array
Special Data Types
The special data types are:
Null, Undefined
Click here for details:
var test1 = 1;
var test2 = "Something";
var test3 = true;
var test4 = {};
var test5 = new Array();
var test6 = new Date();
var test7;
var test8 = null;
alert(typeof (test1)); //number
alert(typeof (test2)); //string
alert(typeof (test3)); //boolean
alert(typeof (test4)); //object
alert(typeof (test5)); //object
alert(typeof (test6)); //object
alert(typeof (test7)); //undefined
alert(typeof (test8)); //object
Comments
Javascript has five primitive data types: 1. number 2. string 3. boolean 4. undefined 5. null
Anything that doesn’t belong to any of these five primitive types is considered an object.
First 3 data types has a corresponding object constructor. For example
var word = "something";
And then as an object:
var word = new String("something");
For object constructor notice the new keyword. It creates object reference.
Another thing to notice that
var greeting = "something";
var word = new String("something");
greeting == word ----> True as their value is same
greeting === word -----> False because there value same but type is different .
As for var keyword being same for all the cases,remember that Javascript is dynamically typed language. That means it resolves data type checking during runtime rather than compile time(like Java, C++ ).
This makes javascript extremely powerful. Though this unique feature has drawback too. Please co through this wikipedia for details: https://en.wikipedia.org/wiki/Type_system#Static_and_dynamic_type_checking_in_practice
Hope this helps.
Comments
According to https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures
Primitive Data types in ES6 are: Boolean Null Undefined Number String Symbol
The other data type which is not a primitive one is Object
Primitive data types are immutable values.
Comments
Primitive Datatypes are 1. Number 2. String 3. Boolean 4. Undefined 5. Null
Non-Primitive Datatypes are 1.Object 2.Array 3.RegExp
Comments
Primitive datatype are type provided by the programming language as the basic building block. like: number,string,null,undefined,Boolean. Primitive datatype get the memory allocation at compile time.
Derived datatype are type which are derived from the existing primitive datatype bundled together like: array,object etc. Derived datatype just get the reference to that memory allocation where value are saved.
Comments
The latest ECMAScript standard defines eight data types:
- String
- Boolean
- Number
- BigInt
- Null
- Undefined
- Symbol
- Object
Note :- Arrays do not belong to this list because they are objects as well. This is a common confusion among developers who assume that arrays are a special data type in Javascript.
Now bifurcate the data type
There are two types of data types in JavaScript:
Primitive values (String, Boolean, Number, BigInt, Null, Undefined, Symbol )
Non-primitive values is also called object references (Object,Array)
Comments
It's simple, just remember primitive data types means the data type which contain a single value, like 1, 'test', true,
Non-primitive data-types means the data type which contain multiple values or complex data called non-primitive like an object etc.
