It's not. It's the "premium" products that have this proprietary bs and branded parts trying to justify the inflated prices. The cheapest printers are all just generic clones with no lock in and mostly generic parts. Practically DIY kits only without the DIY unless something fails.
That's a pretty terrible article on the subject, but I don't have a better one at hand. You could read some shell scripting tutorial or manual or maybe a beginners guide to Unix. A decent one should explain job control well.
But basically, in a script or command line, an ampersand ends a command and runs it in the background without waiting for it to finish before running the next command. A semicolon works the same but waits on the foreground.
I think I've used one Electrolux somethingsilenceorsomething and it really was startlingly quiet and pretty good for normal use. No idea how durable it is, but it sticks in my mind as the only genuinely quiet vacuum I've ever used.
That's the surprise we've got in many countries in the last decade or two. Turns out there's a lot of people all around the "west" who want nazi and tribalist governments despite their history and identity being in plain sight.
Instantly reminded