A small part of it is that your events are basically constant streams of data (think arrays) you can map, reduce, and filter (among other functions) and then present. Here is a short article on it:

https://medium.com/@andrestaltz/2-minute-introduction-to-rx-...

This is a discussion over the controversy of calling stuff FRP in academia vs. real world:

https://medium.com/@andrestaltz/why-i-cannot-say-frp-but-i-j...