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Santhi Sri Jamisetty
Santhi Sri Jamisetty

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Variables and Datatypes In JavaScript-series-1b

JavaScript is loose typed which means you don't need to specify the type of variable while declaring it, which differentiates other languages like Java, C++ wherein you need to specify its type while declaring a variable.
Ex: In JavaScript var age = 10;
In Java

int age = 10; specify the type of variable.

The Primitive Type datatype includes :

1)String ex: var color = "orange";
2)Number ex: var salary = 100;
3)Boolean(to check true or false) ex: isCatSleeping = true;
4)Null ex:refer to series 1a where in the table you see the "Registration Cost " for Andy Young has no value.
5)Undefined ex: var myCar; the variable myCar declared but has not set any value.
6)BigInt(recently added). These are for micro-precision timestamps.Please refer to MDN JavaScript for further reading.

Note:To check the variable dataype use this function called typeof();
Ex: var color = "orange";
output is "string".

The other called complex/composite datatypes because these include Objects as well as the Primitive types.
Objects includes Array
Function etc.
We will learn about object-oriented programming later.

Modern browsers use ECMASCRIPT to overcome the scope of the variables. We will learn about it in series 1c. where we learn about hoisting, let, const etc.

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