Arduino Nano vs Arduino Nano V3, R3, etc

Hello,

I've seen some info online about Arduino V3 R3 etc, but what is the difference between each Arduino Nano versions?
Do they have different pinout's?

AFAIK, there is only one "official" Nano version. There are minor differences with clones, the most notable is the USB to serial converter chip. The true clones use the FT232, the cheap knock-offs use the Chinese sourced CH340. I prefer the CH340 as it is more reliable than what might be a counterfeit FT232 (Google it). Personally, I've bought dozens of different FT232 modules from China without issues, a half dozen Nanos with FT232's without issues. Maybe I'm just lucky. I've never seen a clone Nano with a different pin-out.

The situation with the Pro Mini clones is far different, there are so many variations it's almost impossible to catalog them with no official pin standards being followed even though it is an open source design.

I prefer the FT232 modules, purchased from a reputable source, i.e. NOT ebay.
Mouser.com has MIKROE483 modules, great for embedding on a board.
Tinyosshop.com has FT232 modules with micro-USB and mini-USB connectors, and a jumper for 3.3V or 5V IO.

I won't use the CH340 chip in a design because the reputable distributors - Digikey, Mouser - don't carry them, and I won't use parts I can't buy.

I bought a pile of off-brand Nanos a while back that use the CH340, it's given me a problem on installing a few times, Windows likes to kick out the driver for some reason, but other than that I have had no problems with them and at about $4 each, it's hard to beat. I've done a fair number of projects with them and have seen no problems, nothing different in the pinout or controller and they run fine continuously or on a start/stop basis.

an "Uno R3" in an enhanced Uno, which added extra pins for I2C (and maybe some other changes), relatively recently.
The "Nano V3" is much older; I think it got that version number when it went from an ATmega168 to an ATmega328, and all the versions currently available are essentially the same (except for the different serial controllers that others have mentioned - which SHOULDN'T make a difference.)

Nice,

So I only need to watch out when I buy a pro mini,

for now am not worried about the chips the Nano comes since any chip will work, although I might need to have that in mind in the future,

thank you for your replies, everyone!

@CrossRoads LCSC has those chips.