Windows 10

[emjay]

SSDs use wear leveling algorithms for longevity though, I don't think SD cards bother because in most cases, there just isn't enough I/O to matter.  Might not matter on a typical consumer system, but I wouldn't use a SD card for primary storage on anything important.

I had to do some research on that myself, because of getting a laptop with an SSD. As far as I understand it there are two types of wear levelling, dynamic and static. SD cards use dynamic and SSDs use static. The idea being that with dynamic wear levelling it only moves around the files that are constantly changing but any static files will not be reallocated. So in other words if you put a file on and leave it there, the write counts for the blocks that it uses will not increase whereas they will for any non-static files, resulting in uneven wear across the whole drive and failure when enough of them fail. Static wear levelling on the other hand moves all files around, even static ones periodically, with the aim of all blocks reaching their write count limit and failing at roughly the same time. So in this case of putting an OS on a SD card I'm not sure what the wear implications would be... there'd be plenty of static files but also a lot of activity. I guess, like an SSD, the more free space you leave on the drive the longer it's going to last whichever type of wear levelling it uses. In other words, for an OS, bigger is better.