I studied about I/O in my Computer Organization subject and i found some interesting questions. I would be please if PROs able to enlighten me.

Question 1:
Memory-mapped I/O and port I/O. Both of them are different design right?
Is the port I/O is also known as separate I/O space(which has it's own special instructions)?

Question 2:
Intel processor generally use port I/O design? Why?
How about Motorola?

Question 3:
Any advantages and disadvantages between Memory-mapped I/O and port I/O?

Thx~! Computer nerds RoX.