You may install software on up to two computers. These two computers can be Windows, Mac OS, or one each.
If you install on a third computer, it will request you to de-activate on the other two computers. You can then reactivate one of the previous two computers, and use Creative Cloud apps on it.
If you regularly need to use the Creative Cloud on more than two computers then it would be best to purchase an additional subscription. This is the same licensing btw which we have for our prepetual product. An advantage though for Creative Cloud over the prepetural product is that you can install on Mac and Windows with the same subscription!
It seems like you should be able to load on as many devices as you want. Since you can only work on one machine at a time the Adobe ID would check. Since we now pay perpetually for use of the software, what device we use and where we use the product should have more flexibility then two machines.