Seconding folks re: some of the advantages on latency, efficiency, etc. I also wouldn't describe it as "just" a emulator, or to think of it as something interp

Seconding folks re: some of the advantages on latency, efficiency, etc. I also wouldn't describe it as "just" a emulator, or to think of it as something interpreting / emulating some digital logic. It's much lower level than this, in that it is actually implementing your design in real hardware (consisting of lookup tables / logic gates / memory cells, etc. all "wired" together. As such, they can be useful not only for implementing some custom bits of glue logic (e.g. interfaces which need high speed serialization / deserialization of data), or accelerating a particular calculation, but also for anywhere you need to have really deterministic performance in a way that isn't easy or even possible to do in software / an emulator alone.