Paul, that's 'UEFI firmware'.
And yes, I did warn you about purchasing this particular computer, yet you went ahead anyway, now you first hand see what I was telling you. But on mine, I was able to disable Secure Boot, it's the first thing that I do with any newer computer that I check out.......as a favor to the owner. No harm is done, in fact, bootable utilities like rescue CD's or Flash drives won't boot with it enabled. The only thing that Secure Boot does is 'places handcuffs' on the computer, so that you can't use it the way you wish.
Now, before we go to bashing UEFI, first off, it's not the fault of the standard as to 'why' you can't install Linux on that PC, rather it was how Samsung implemented it beginning in 2012, whom by chance are out of the business of building Windows computers. Horrible firmware issues with their later models, look at the one in my bottom Speccy sig. Samsung had to replace the MB because it was bricked after a UEFI firmware update (not to be confused with a BIOS update, the standards are different, though the procedure may appear the same). It left the notebook in a permanent boot loop cycle less than two months after purchase, and rather than let the battery drain (which may or may not have helped), my relative plugged while awaiting a call from a Samsung rep & it sat in that state until the heat generated from the endless boot loop finally destroyed the MB.
Anyway, she got the notebook back two weeks later, with a brand new, factory updated MB & was told 'there would be no more firmware updates of this type available'. So far there hasn't, and to think, it cost over $1,300 after taxes new & it's still two months from being 3 years old & I've had it for 6 months or so, was given to me for setting up a new notebook, printer & new wireless router (was given the one year old of that also), but don't have any 'AC' devices & the brand of router may not play well with my VoIP service. So will keep the router, which cost more than the one I purchased early this year, and when it goes, will have another, with more features to take it's place. All I would need to do would be purchase a few 'AC' wireless cards for upgrading what I have for about $25 each (new pulls from corporate workstation notebooks).
Furthermore, Microsoft didn't even come up with the technology, though they later purchased the rights to it before Windows 7 was released, seeing potential in it. It's been greatly altered since that time. Note that everything Windows does has a left slash (\), if it were Linux, would be a right one (/). That's the proof that Microsoft altered it.
At least you were lucky (or maybe you weren't?) to have Windows 10 installed, it won't run right on my Samsung & furthermore, removed all Samsung software from the OS, which I didn't like. Hopefully you have a local & not a signed in OS, where Microsoft can access your data anytime they wish, they even use some users GPU's to upload data (& this was proven on this forum with snapshots). If GPU's can keep the worlds virtual currency in Bitcoin flowing, surely Microsoft would figure out a way to make the same work for them.
Windows 10 Pro even slowed my main PC, AV & AM scans were taking 2x longer & superAntiSpyware scans that were taking 17-21 seconds to complete, over a minute. What a resource hog of an OS, Windows 8.1 has over 7 years of life left (until early 2023), I don't need Windows 10, and I also don't sign into my 8.1 Pro w/Media Center OS's, just use a Local account.
Yes, you can run any version of Linux by VM, at least Samsung didn't mess that up.
I told you so months ago, thought you were going to choose another computer.
You must have forgotten, or maybe think there wasn't substance to what I said. If I didn't have the computer myself, wouldn't have been able to inform you. Yet I can live with 8.1 Pro w/Media Center, nice running notebook for being less than 3 years in use that I got as a gift for a day's labor. Being disabled, anything I do is volunteer work on those terms. If someone wants to give me something for my time, then am thankful for any donations received. That's why I only help close friends/relatives, they know my situation & how to make sure I'm looked after. I'm allowed to do as much volunteer work as I want.