I'm new(ish) to Linux so apologies if this is a stupid question.
Only stupid answers! As per JamesH they are mostly 'just there'. However you are correct there are peripherals that don't have Linux drivers and/or take a lot of work with Dr Google to get them to work. I moved to Linux about 7 years ago and so can't relate properly to the state of Windows today, but on my PC
- 2.4GHz wireless keyboard/mouse works out of the box
- all pendrives/external HDD work out of the box
- IDE DVB-T TV card works out of the box
- old DVB-T USB stick needed firmware copied off the supplied "Windows" CD and put in the correct Linux directory
- (very old) scanner also requires firmware file to be retrieved from Windows and put in the correct directory
- Mobile broadband dongle works out of the box.
- Wifi USB stick works out of the box
- mobile phone (very old - Sony Ericsson K770i!) needs a line added to a config file to be able to sync diary/contacts/messages
I have to admit that I only once got the remote control on my TV card to work but that is more because I am useless at the IR side of Linux. And can run the TV just fine without a remote.
Certainly worth doing a bit of homework before parting with cash for any peripheral, but in last 2 or 3 years things have become almost painless. My (Linux) distribution is SuSE, one of my most common search types on Dogpile is "suse product name and model number".
USB keyboard/mice it is hard to conceive a major problem. For sure getting all 57 buttons on some of todays gaming mice to work properly would be a challenge, but 3 button and scroll are fine
Daily driver: Pi3B, 64GB Samsung Evo+ @100MHz, DVB-T, onboard WiFi for internet, BT/USB dongle for KB/mouse, 250GB HDD via USB for media, Raspbian Jessie Lite with Openbox desktop.
Museum: Pi B