Review
I decided to also do the TypeScript Essential Training course because the author is the same as Learning Typescript and recommended this one as a more complete and detailed dive-in. My review considers that same path and judges accordingly the contents of the present course.
This is an intermediate training of more than 4 hours, divided into 9 chapters. The first four ones are basic setups, a basic introduction of Typescript and typing, and quite a few ES2015 concepts. As such, if you already know some basics and/or are up to date with ES2015 or ES6, I suggest you to directly skip the first 4 chapters and start from the fifth one. Still, the remaining chapters cover in good detail not only main features but also more advanced topics like function overloads, abstract classes, generic constraints, namespaces, sourcemaps... The examples presented are more akin to real world scenarios and the sample application (a TODO webapp) is small yet appealing to see how to migrate and add typing.
The explanations of how Typescript compiles to Javascript certain features are sometimes very interesting, like namespaces being implemented using IIFEs or visibility access modifiers not really being enforced at runtime. As the course is from 2016, the ECMAScript version was yet ES2015, and even some features available on that version are not always present in the sample code, but in general I still found the contents useful.
All in all, I think I extracted quite a few learnings from the course.