I’m fairly new at Linux, but this amazed me. When auto-installing Ubuntu-Mate, the installer looked at my hdds and decided to partition and install on sdb instead of sda. It also automatically adjusted GRUB so that I could choose which OS to use, on either HDD. At first, I thought it should have just partitioned sda, because it is a 1TB HDD and has plenty of room. While the sdb is only 250GB and is my backup drive. After thinking about this, I thought what if one of the HDDs failed? The way the auto-install implemented the installation, I can still boot and run the system even after a HDD failure. I think my logic is good about this. Please correct me if I am wrong. Sorry if I’m wasting space or boring you, but I was very impressed with this installation.
I'll take a stab at this 
Pretty much that the way linux works, it tries for the best choice.
More control can be gained by..
also
Post on, I'll try to to help some more
Yes, I know about the install using “something else” method. I was just complimenting the developers on a job well done. It was nice to see the extent of the thought that went into the auto-installation process; unlike another OS that just installs itself by wiping out all other partitions on the disk that it’s being installed on. I feel that the method used by the developers not only made the installation easy. But, in the process made my system more secure against not being able to boot upon a HDD failure, by installing MATE on sdb. I may have neglected to say, earlier, that my other OS is installed on sda. Anyway, I am very impressed with both MATE and Ubunutu.
Hi @OldBoots,
“Auto Install” can ruin someones PC if they aren’t paying attention!, by that I mean it can erase all their personal files and data!. I know you know this but others reading this thread might not!. 
Thank you for pointing that out. I would not want to feel responsible, in any way, for someone losing their files and data.