Yes
Yes
Yes
As blimeycharlie says, it’s not really necessary these days, but I do recall one Christmas I got a set of four plugs from my mum - red, blue, green, yellow - to stick on the ends of stuff like TV, radio, Commodore 64, fan-heater (something like that) so I was sure to know which device I was unplugging without needing to check. Yes people, in the early 80s things were simple.