“TypeScript 4.0 represents our next generation of TypeScript releases, as we dive deeper into expressivity, productivity, and scalability,” Microsoft’s Daniel Rosenwasser writes in the announcement post. “With TypeScript 4.0, there are no major breaking changes. In fact, if you’re new to the language, now is the best time to start using it.”
For those unfamiliar, Rosenwasser has a nice explanation of the why of TypeScript:
You can learn more about TypeScript on the TypeScript website.