title: What are Typescript features?
body: <p>I edited tag definition here on stackoverflo but it was rejected. so i want to know if i dont understand exactly what is typescript? </p>
  
  <p>tag description says: 
  TypeScript as a language extension adds (amongst others) the following features:</p>
  
  <ul>
  <li>Type annotations and compile-time type checking</li>
  <li>Namespaces</li>
  <li>Interfaces</li>
  <li>Enums (to define a set of named constants)</li>
  <li>Generics (classes, types, and functions that can work over a variety of types)</li>
  <li>Await (suspends the execution until an asynchronous function return promise is - fulfilled)</li>
  <li>Abbreviated "arrow" syntax for anonymous functions</li>
  <li>Optional parameters and default parameters</li>
  </ul>
  
  <p>so how exactly add typescript async await feature and arrow functions? for me it is pure javascript (ES) syntax, </p>