#Rufus vs universal usb installer iso
#Rufus vs universal usb installer windows

#Rufus vs universal usb installer windows

And even if the image does use a file system / partition mapping (remember, Windows version prior to Win10 1703 could not mount more than one partition from a drive with the 'removable' attribute, which most USB Flash Drives will have) that lets users access the data from Windows, by writing in DD Mode, you are only ever going to be able to use your drive up to the maximum size of the original image.

Besides, DD writing presents major drawbacks for Windows users in that the image may be written using a file system that Windows does not support, in which case many people are going to be confused as to why they are no longer able to see or access the content of their USB in File Explorer, or, in case the image contains an EFI System Partition, why they suddenly only see a super small FAT32 partition with next to no content, from what used to be a large USB. Especially the Windows ISOs aren't, so the method above, which we call 'DD Mode', cannot be applied all the time. Now, once you managed to clear the drive, write the data, and made sure that nothing should have been able to modify it behind your back, then you 'should' be able to rely on the makers of the image to have sorted the USB boot, so your job is done (or at least, if it doesn't work, it's not your issue). Also, you may have to work around some Windows own quirks ( quirk #2, mostly seen with Windows 10), where Windows will prevent you to write whatever you want unless you first cleared the drive properly (and by properly, Microsoft means using one of the 3 methods that are supposed to clear the partition tables and whatnot, but that are temperamental enough so that only one tends to work as expected). except ( quirk #1) it also first needs makes sure that there doesn't exist another process that is currently trying to access the drive in write mode, since, to reliably write to the drive, you really don't want to leave the door open for something else to also have kept some write access opened, as there is no telling how they might arbitrarily change the data you just wrote behind your back, and screw up the boot.

#Rufus vs universal usb installer iso

If the source is a DD (pure disk image) or ISOHybrid image (mixed ISO and disk image), then this is the simplest case: Rufus does write it, bit for bit, without any conversion, onto the USB drive.

Well, that varies a lot depending on the type of source image you have and type of computer you are trying to boot. Glad you asked, because a lot of people seem to think an utility like Rufus doesn't do much ( 'Why use Rufus when you can just use diskpart ?'), and fail to realize that there is usually a lot more happening behind the scenes because of all the many quirks that are inherent to what can mostly be described as trying to fit a round peg (an ISO image) into a smaller square hole (a USB drive). (Obligatory: Thank you very much for the gold, kind stranger!)