What is the difference between Reactive-Extensions/RxJS and ReactiveX/rxjs
RxJS 4 is hosted on: https://github.com/Reactive-Extensions/RxJS
RxJS 5 (https://github.com/ReactiveX/rxjs) replaces RxJS 4 and is relatively compatible with RxJS 4. README.md on gtihub says:
Reactive Extensions Library for JavaScript. This is a rewrite of Reactive-Extensions/RxJS and is intended to supersede it once this is ready.
RxJS 5 is completely written in TypeScript and compiled to both as ES6 and ES5 (as a bundle in UMD format).
There's also RxJS 6 currently in development.
Also, RxJS 4 is now called rx and npm while RxJS 5 is rxjs now. The scoped one @reactivex/rxjs is probably just an older npm package (they both come from the same repo).