Differences Between JavaScript And TypeScript

In this blog, we will see some of the differences between JavaScript and TypeScript.

Javascript	Typescript
It is a scripting language.	It is an object oriented programming language(not pure).
There is no static typing. ex: var num.	Here it is static typing (We can declare a variable in multiple ways). ex: var num : number.
It doesn't have interfaces .	It has interfaces.
It has no optional parameter feature.	It has optional parameter feature.
It has no Rest Parameter feature. No generics are supported	It has Rest Parameter feature. Supports generics.
No modules support. Number, string etc. are the objects.	Supports Modules . Number, string etc. are the interfaces.

Example code for TypeScript & JavaScript is given below.

TypeScript 

class Greeter {
    greeting: string;
    constructor(message: string) {
        this.greeting = message;
    }
    greet() {
        return "Hello, " + this.greeting;
    }
}
JavaScript: var Greeter = (function() {
    function Greeter(message) {
        this.greeting = message;
    }
    Greeter.prototype.greet = function() {
        return "Hello, " + this.greeting;
    };
    return Greeter;
})();