What is the nuance of 32-bit micro and 32-64 wasps?

Question

Microcontrollers

Good afternoon, tell me what does 8 or 32 bit mean for MK and what will OS 32 or 64 bit mean for them?
What is the nuance of choosing an OS for MK?

Answer 1

Memory addressing -> maximum available MK memory and native arithmetic. In principle, 8-bit can also turn 128-bit numbers, but for a long time.