The main concepts are:
Any part of the store is also a store
Reaction is a function that can use values from store.
It is supposed to be called again in response to changes in the store it was reading from during previous call.
Act of automatically or manually running reactions in response to store changes
Selectors allows us to perform some expensive calculations or async requests and reuse the results multiple times.
If selector reads from any store - it will automatically re-calculate it's value after related store values are changed
View is special kind of react component that will automatically re-render itself if any store value it used during the render changes
React re-render could also be called reaction if used in context of react & statek.