I have been working with TypeScript for almost 2 years, using it in both frontend and backend. In my opinion, TypeScript makes developers life easier, especially when they have a OOP background.
But why TypeScript?
It’s very important to have types when writing complex applications or libraries. Types can avoid mistakes and, in my opinion, make the code more readable. Secondly, TypeScript is maintained by Microsoft and they are doing an excellent job updating the language to support the lastest EcmaScript features. Lastly, TypeScript supports all features from ES5, ES2015 and much more: types, generics, enums, interfaces etc…