to commonly asked questions.

m1 chip and hard drives

I need to buy a backup for the new desktop - do these new mac’s have some special requirements for external hard drives? I ask because my mom got a new laptop as well and she was reading about some adapter she has to get when she buys a backup. Your expertise is appreciated!

No special requirement really. You can use any hard drive with a USB to USBC adapter. You can, of course, just buy a USBC hard drive but there’s really no need to spend extra money. Since this particular drive would just be for backup, performance gains using USBC would not be noticeable.
This image is a theme.plist hack