New book on TypeScript by Dr. Axel Rauschmayer, who also wrote Exploring ES6 (and a few other books on JavaScript).
This book consists of two parts:
- Part 1 is a quick start for TypeScript that teaches you the essentials quickly.
- Part 2 digs deeper into the language and covers many important topics in detail.
This book is not a reference, it is meant to complement the official TypeScript handbook.
The first part is freely available.