Difference between MAX 485 iC

Using Arduino General Electronics
#1

Dear all.

I would like to major difference between these ICS.

1)Max 485 Low power Slew rate limited

2)SN75176 :Differential Bus Transceiver

  1. ADM 2483 DifferentialBus Transceiver
    http://www.analog.com/media/en/technical-documentation/data-sheets/ADM2483.pdf

ADM 2483 is Isolated type power supply. I could not able to differentiate functionality

#2

Why ?

#3
  1. Is RS485 standard
  2. Is RS422 standard
  3. Is RS485 standard but is isolated between the two sides.
#4