Null- and undefined-aware types TypeScript has two special types, Null and Undefined, that have the values null and undefined

Union types Overview Union types are a powerful way to express a value that can be one of several types

Type parameters as constraints With TypeScript 1.8 it becomes possible for a type parameter constraint to reference type parameters from the

async/await support in ES6 targets (Node v4+) TypeScript now supports asynchronous functions for engines that have

Protected The new protected modifier in classes works like it does in familiar languages like C++, C#, and Java. A protected

ES6 Modules TypeScript 1.5 supports ECMAScript 6 (ES6) modules. ES6 modules are effectively TypeScript external modules with a new syntax:

JSX support JSX is an embeddable XML-like syntax. It is meant to be transformed into valid JavaScript, but the semantics of that transformation

Performance Improvements The 1.1 compiler is typically around 4x faster than any previous release. See