If you are interested in TypeScript and would like a free e-book to help you learn to write and understand TypeScript, please look at TypeScript Deep Dive by Basarat Ali Syed.
For the low, low price of free, you get 179 pages of pure awesomeness. Chock full of source code examples and clear, concise explanations, TypeScript Deep Dive will help you learn TypeScript development.
If you aren’t sure you are interested in TypeScript, consider this:
TypeScript is one of those alternatives worth your consideration. It’s open source, and we like that. It’s trustworthy also, because it is supported by a big organization (Microsoft) with an investment in making developers successful. Just like NativeScript is supported by Telerik.
Learning TypeScript isn’t scary or even hard. It’s a straightforward way to add the necessary items to your code to get better code organization, compile type error checking and amazing intellisense-type help from your IDEs.