Introducing TypeScript – Microsoft’s new open source JS language

TypeScript is a language for application-scale JavaScript development.TypeScript is a typed superset of JavaScript that compiles to plain JavaScript. Any browser. Any host. Any OS. Open Source.

http://www.typescriptlang.org/#Download

Starts from JavaScript, Ends with JavaScript

TypeScript starts from the syntax and semantics that millions of JavaScript developers know today. With TypeScript, you can use existing JavaScript code, incorporate popular JavaScript libraries, and be called from other JavaScript code. TypeScript compiles to clean, simple JavaScript code which runs on any browser, in Node.js, or in any other ES3-compatible environment.

Contribute

Read the specification in doc or pdf

Discuss and provide feedback on the language.

Play with the bits and file bugs.

Join the #typescript Twitter discussion and follow the CodePlex project.

Learn

Tutorial – Best way to get up to speed on TypeScript.

Forums – Great place to get help with using TypeScript.