1. Learning Type Script: Hello World

Introduction: Typescripts describe the shape and behavior of your code and what value will be when we run our program.

As already we are familiar with javascript we know the below code

const myvar= "Hello World!"; 
myvar.toLowerCase()        

The above code will give you result with all lower case right?

Now check the below code

const myvar= "Hello World!"; 
//calling myvar
myvar();        

What do you think about the above code? Is it will run correctly?

It will through an error like TypeError: myvar is not a function right?

So it would be great if we can avoid this type of mistake

So we can come to TypeScripts

TypeScript can catch bugs when we make mistakes in our code. That's great, but TypeScript can also prevent us from making those mistakes in the first place

We've been talking about type-checking, but we haven't yet used our type-checker. Let's get

acquainted with our new friend tsc , the TypeScript compiler. First, we'll need to grab it via npm.

Before running the below command pls check whether your node.js is installed or not.

    npm install -g typescript        

Now can start our first typescript program.

 console.log("Hello world!");