Hello to everybody, I have signed up just now.
I have a trivial question, inside a (for example) BLE module is there a microcontroller (PIC)?

What is the function of the PIC?
I imagine it is integrated in the BLE module, but sometimes I read is possible to couple with external PIC.

I t is not clear to me...can you explain me the basics of the architecture?

Thanks, Glenn.

PIC is just a microcontroller architecture, like AVR. One could interface a BLE wireless chip to a PIC (just like one could interface it to an AVR or other microcontroller - there's nothing special about PIC). There may exist boards or modules which integrate a microcontroller (like a PIC) with a BLE chip; the specifics of how this would work would depend on the specific implementation (ie, whether you're meant to reprogram the PIC, or if it's running their firmware just dedicated to providing an easier interface between the BLE controller and another external microcontroller running the application code)

This is the Arduino forum; there are no Arduino boards or third party hardware packages that support PIC (IIRC there's no free compiler), so if you have more detailed PIC-specific questions, you would get better answers on a forum dedicated to PIC.