JS Variable – Schools

Programming is about manipulating data / value. Data / Value is stored in variable. To create variable in javascript using keyword var . For example var myData = 1; There are 7 data type in Javascript :

Number
String
Boolean
null
undefined
Array
Object

Number

<!DOCTYPE html> <html> <body> <script> var MyNumber = 5; alert(MyNumber); alert(typeof MyNumber); </script> </body> </html>
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String

<!DOCTYPE html> <html> <body> <script> var MyString = "Hellow World"; alert(MyString); alert(typeof MyString); </script> </body> </html>
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Boolean

<!DOCTYPE html> <html> <body> <script> var MyBoolean = true; alert(MyBoolean); alert(typeof MyBoolean); </script> </body> </html>
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Null

<!DOCTYPE html> <html> <body> <script> var MyNull = null; alert(MyNull); alert(typeof MyNull); </script> </body> </html>
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Undefined

<!DOCTYPE html> <html> <body> <script> var MyVar; alert(MyVar); alert(typeof MyVar); </script> </body> </html>
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Array

<!DOCTYPE html> <html> <body> <script> var MyArray = [1,2,3,4]; alert(MyArray); alert(typeof MyArray); </script> </body> </html>
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Object

<!DOCTYPE html> <html> <body> <script> var MyObject = {'Name':'Albert','Age':15}; alert(MyObject); alert(typeof MyObject); </script> </body> </html>
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