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1/ So maybe here's a good chance to talk about all the markings on a microSD card. What do all these codes mean?? 
2/ First, is the vendor. Toshiba/WDC(SanDisk) are the largest maker, working in partnership. Samsung is the next largest. Micron/Intel had a partnership and were #3, but they've disolved it.
3/ The maker of the card combines lash with a controller. The brand you buy, like Lexar, Patriot, Kingston, etc. may not have been the actual maker of the card, they just put their name on it. You can find the actual maker by looking (on Linux) in /sys/block/mmcblk0/device/cid
4/ The vendor then puts some sort of model name on it, like "Extreme", "Ultra", "Extreme Plus", "Extreme Pro". I can't decipher their meaning.
5/ Given a vendor and model name, the product is actually highly variable, as this screenshot shows with different support for A1 and A2 speeds in the same model. They make a batch, and each batch will vary a lot from each other. Check that 'cid' field to find when made.
6/ Thus, when you read online benchmarks of a "SanDisk Extreme" microSD card, it won't mean much to you 6 months later when the cards on the market are quite different.
7/ So what is "SD" vs "SD HC" vs. "SD XC". Essentially, it's just whether the file system comes preformatted as FAT16, FAT32, or exFAT. This doesn't matter when sticking into a phone/computer, but cameras with old firmwares will have compatibility issues.
8/ exFAT is Microsoft's extension of the FAT file system from 2006 and was encumbered with trade secrets and patents, so actually was actually hard to read on macOS and Linux. Now it should work just fine. Cards 64gigs and larger use must use exFAT/SDXC.
9/ You can reformat the cards as Ext4 or NTFS, but FAT is actually better suited for external media like flash cards. The internal wear leveling algorithms are assuming you are using FAT.
10/ That roman numeral indicates whether the card uses the UHS-I, UHS-II, or UHS-III interface. Your laptop supports UHS-I and below. Your Raspberry Pi supports the slower (25MBps max) pre-UHS-I standard. Only high-end cameras use UHS-II or UHS-III.
11/ UHS-I goes up around theoretical max 100-MBps transfer rate, but that doesn't reflect actual speed. Vendors would be intentionally misleading. So the U1/U2/U3 logo (U wrapped around digit) means guaranteed MINIMUM transfer speed of 10/20/30 MBps respectively.
12/ But even if transfer of 30MBps over 1-second is guaranteed, there may be many long pauses of several milliseconds that will cause video to stutter. Thus, the V10/V30/V90 video standards, guaranteeing smooth flowing transfer rates of that number of MBps.
13/ Computer apps, like on Android phones, or your Raspberry Pi, don't stream photos/music/video, but instead want to do frequent random access. This has always sucked for microSD. Modern cards now may have an A1 or A2 rating, guaranteeing a certain IOPS speed.
14/ thus, when buying a microSD card for Android apps or for booting a Raspberry Pi, always choose an A1 or A2 card.
15/ Some cards have a C10 rating, a C wrapped around a 10. That meant a minimum of 10MBps using the older pre-UHS-I interface. Pretty much all new cards support that, so it's redundant.
16/ Some cards have an x rating, like "1000x", meaning a thousand times faster than a CD-ROM. This was always a stupid rating and not one you find on reputable cards, just cards trying to impress you.
17/ Some cards are marked "endurance", intended for heavy duty recording for surveillance cameras. Flash doesn't like frequent overwrites, it wears out. I'm not sure what "endurance" rated cards are doing to handle more frequent overwrites.
18/ If your Raspberry Pi application writes frequently to flash, the way you'll watch it degrade is that reads/writes get slower and slower. If that's happening to you, you'll need to upgrade to the "endurance" flash.
19/ Lastly, what does "SD" stand for? I have no idea. I mean, they say "Secure Digital", and it's supposed to support DRM for music files, but as far as I can tell, that's always been a non-feature.
