NotSpaghetti
My US born baby wore both nappies and diapers.
UK nappies being, highly absorbent terry towelling fabric finished into a large square, (maybe 24"x 24"). These were folded (in my case) into variations of trangles of kites.
I really only used them as nappies and not as a burping cloth for example as they are bulky.
My US diapers were also cotton but not terry toweling, and not square. They were very soft and useful - a bit like a huge table-napkin.
Most diapers that we had were cotton birdseye which is a weave with a little (very low) texture that's pretty absorbent. They were bigger than UK nappies and rectangular and so were folded into various rectangles before pinning. They gave a slimmer shape to the baby as not so bulky on.
Some of my diapers however were the newer "prefolds" these had a pre-sewn thick panel down the middle composed of several layers of this same soft cotton material.
Here's a traditional UK nappy, a birdseye cotton diaper and a prefold diaper. (See photos - found online..)
The diapers I used were 100% cotton-flannelette.
Large sheet style, tightly woven, thick and super-absorbent, they fit from newborn to toddler, and required folding from scratch.
Like most other things, I'm sure there were different grades of cotton diapers, some thicker and more absorbent that others. The ones I used were what everyone I knew used.
Folded down for infants and smaller babies, folded down less for bigger babies and toddlers. I preferred following in my own mothers footsteps, so I always doubled the diapers for more absorbency.
A diaper pin on each side, rubber pants over top. Made for a bulky bottom, but boy, did they ever get the job done, and very well may I add!
A set of diapers 4-6 dozen would last through the diapering stage of two babies before starting to get threadbare and needing replaced, but the old threadbare ones didn't go to waste. They made for the best general all-purpose household cleaning and wiping cloths ever!
I remember prefolds from my babysitting days, though the old-fashioned fold-from-scratch version were the most popular and widely used, at least in the homes where I babysat.

