I rad, that we can create numbers as:
var num = 10;
and:
var num = new Number(10);
may i use only first variation of declaration?
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Tarun Dugar
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Nikita Shchypylov
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Possible duplicate of [primitive types / reference types in Javascript](http://stackoverflow.com/questions/14443357/primitive-types-reference-types-in-javascript) – david Jan 28 '16 at 09:38
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Yes, use the first one always, as it returns a primitive value.
The second method looks like it returns a primitive value but it doesn't. Infact, it returns an object with a boxed primitive value.
To explain this, lets declare two variables:
var a = 2;
var b = new Number(2);
The expression a == b will return true since JavaScript coerces b to a primitive value of 2. However, the expression a === b will return false as the types are different: a being a primitive and b being an object.
Tarun Dugar
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Exactly. The following demonstrates: var num = 10; typeof num; "number" var num = new Number(10); typeof num; "object" – minitauros Jan 28 '16 at 09:39
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yes, i am new in js so it takes my head away when i ma trying to understand both.so,1st var is better to use? – Nikita Shchypylov Jan 28 '16 at 09:41
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not 'better' but correct way to use it. See my edit to understand the difference. – Tarun Dugar Jan 28 '16 at 09:43
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I would say, yes in general avoid new operator. I use it sparingly myself like for declaring a new date etc. But yes, I never use 'new' for primitives. – Tarun Dugar Jan 28 '16 at 09:46
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Why does `var a = 10;a.toString();` work and not `10.toString()`? What is the difference? – E. Sundin Jan 28 '16 at 09:49
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Found the answer [here](http://stackoverflow.com/a/4046367/3951400) :-) Thanks anyway. – E. Sundin Jan 28 '16 at 09:58
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