Aconis WD True Image

I would like to know in simple terms what the main difference in Acronis Western Digital True Image cloning options:
1. Replace disk in this computer (disk will be bootable)
2. Replace disk in another computer (disk will be bootable)
The manual does not explain it. Does it have anything to do generic drivers or windows licensing or unique computer name (on networks)?
Which one makes an exact copy of the original drive?
Does Acronis change MBR to GPT without user consent?
Very puzzled

 

Thanks .. I have an older version Acronis 2014 that clones hard drives without these options.
Here is what the manual says: With the three options.

1. On the Disk Usage step, select how you are going to use the clone.
   • To replace a disk on this machine—the system disk data will be copied, and the clone will be bootable. Use this clone for replacing the system disk with a new one on this PC.
   • To use on another machine—the system disk data will be copied, and the clone will be bootable. Use this clone to transfer all the data to another PC on a bootable disk.
   • To use as a data disk—the disk data will be copied. Use this clone as a non-bootable data drive.

What is the difference between the first two?
I have read somewhere (on the internet discussions) that the first choice "locks" (?) the original hd where as the second choice is the preferred choice since it leaves the original drive as is.
I am looking for more "insider" information on what is actually going on.
Also Acronis WD when installed is always running in the background and doing its own thing... monitoring, backing up, ... etc