Example 01

dynamicallyTyped.js

var myString = "Manoj";
var myNumber = 42;

myString = 32;

console.log('42' - 2); // Result: 40
console.log('42' + 2); // Result: 422 gotcha! (Javascript infers the type of variable at Runtime.)
                       // Javascript assumes you want to concat two strings.
var anotherString = '42'
console.log(parseInt(anotherString, 10) +  2); // Be explicit about your variable types.

// use typeof to determine primitive types.
console.log(typeof 'Manoj'); // string
console.log(typeof 32); // number

var person = {
 name: 'Manoj Fernando',
 age: '27'
}
console.log(typeof person); // object

var people = [{name: "Manoj"}, {name: "Kasun"}]
console.log(typeof people) // object. gotcha! (don't use typeof for instances. use instanceof)
console.log(people instanceof Array) // true
  
}