Question: How to use host callback?

[jamesstocktonj1]

Hi all, I've just started messing around with waPC in Go. I'm curious as to how people are using the host call function. Can it be seen as a kind of bi-directional/ call-response communication channel (like Go's chan). Or is it more used for calling other wasm functions from the host. I'm interested to see all the use cases. Thanks