@Sarah977 we have no-frost and low-frost and maybe a few classic types which have to be defrosted manually
My old no-frost fridge-freezer was fancy 15 y ago when I bought it and it was big (by EU standards at least) and expensive. The whole back was covered in plastic except on the back bottom where the cooler and the ventilator were placed. Most fridges I've seen in stores now, like 95% of them are no-frost, with the same fully covered backside and same cooler on the back bottom. Of course, the dust is collecting quickly around the ventilator and cooler so the fridge has to be pulled out and the vent has to be vacuumed every few months in order to cool properly.
Now I bought low-frost type with a cooling grid along the whole back. No dust problem anymore and it isn't noisy as my old one and many new models ( forums are full of angry customers with new very noisy fridges)
I have also a few older classic fridges and I like them the most. They are simple and cheap, have a cooling grid along the whole back, but the most important is that they are SILENT and they don't need repairs every few years. The only downside is that they have to be defrosted every few months. But OK, nobody is perfect 🙂