Okay first the different types:
-flats- probabyl what you were diapered in. it's those big giant squares of muslin or cotton that you fold down to fit baby
-prefolds- my personal favorite. "prefolded" for you so that the middle panel is 8 layers and the two outer are 4 layers in most types. small amount of folding. very cheap and easy to use once you get the hang of it. fits every baby because you customize. needs waterproof cover
-fitteds- also need waterproof cover. elastic in legs and back, need to be sized to fit baby. can get very expensive. closes with aplix or snaps.
-pockets- what it sounds like. a "pocket" with waterproof outer and wicking fabric inside(like fleece) that keeps baby dry. you stuff with absorbent layer to ABSORB pee. easy. also, can get very expensive and need to fit baby perfectly to avoid leaks. most need to be hung dry but they dry extremely fast. do not breathe in hot weather.
-all-in-one's- usually one of the most expensive. go on and off like a disposable. aplix or snaps closures. take FOREVER to dry but lots of moms like them for outings because the are so easy like a sposie. personally I despise them. they don't breathe well at all in hot weather.
and then there's covers. pul is the waterproof stuff most covers are made of these days. they snap or velcro(aplix) closed. they are waterproof and wash easily in the washer and can be put in the dryer.
wool is my favorite BY FAR! totally breathable in hot weather and warm in the winter. I love longies and shorties because they double as clothing and covers. it's not waterproof but water resistant. you have to hand wash and lanolize(add water resistancy) but you only do it once every 2 weeks or so depending on useage and whether or not it actually gets "dirty" because wool is anti-bacterial and will not hold smell once aired out. there are also wool covers if you prefer a snapping alternative under clothing but be warned, it's bulky. that's why I prefer knit or interlock wool(like wool fabric) as a clothing item.
nylon is the stuff those gerber plastic pants are made of. lots of those pull-on covers are made of the stuff. again, doesn't breathe well, like pul. but that may be your choice.
My wash routine:
dry pail everything together. dump whatever dumps into toilet, leave whatever doesn't.
cold wash with a quick squirt of Dawn dishwashing soap and tea tree oil to disinfect
cold rinse at end with vinegar to break up any remaining soap residue
hang dry outside if not raining, inside in basement if icky outside
My daughter wears mostly prefolds and wool. It's what works for us and what we'll do on this feb 2008 baby too. Cheap and breathable, always dependable. Here's some pics if you are interested in what our system is:
prefold with a snappi to close
http://i40.photobucket.com/albums/e2...s/05_31_12.jpg
wool interlock shorties from Wild Child Woolies on HyenaCart(angela is my favorite for interlock. she's a sewing GODDESS and her stuff is amazing!)
http://i40.photobucket.com/albums/e2...gs/05_10_2.jpg
knit wool by me
http://i40.photobucket.com/albums/e2...gs/05_09_6.jpg
interlock wool soaker by Luxe Baby. it's so trim only because the prefold underneath was BARELY on it was so tiny. this is not indicative of trimness
http://i40.photobucket.com/albums/e2...s/05_26_30.jpg
knit wool pants by me with prefold underneath
http://i40.photobucket.com/albums/e2...gs/05_13_0.jpg
pul covers(proraps)
http://i40.photobucket.com/albums/e2...gs/06_17_0.jpg
bumgenius 1.0 one-size pocket with a microfiber insert
http://i40.photobucket.com/albums/e2...gs/06_05_4.jpg
way back when when we actually used fitteds. i don' have any now. it's an SOS(suzie's one size)
http://i40.photobucket.com/albums/e2...s/110_1039.jpg
wish I had some aio's to show you but again, I don't have any. I think the last one she wore she was maybe 6 weeks old. I hate the things.