I used to crochet, but that has been eons ago. Not even sure if I still know all the different stitches in that anymore, think I have forgotten some of them now. LOL, but I used to buy just the basic average yarn. I think knitting is pretty much the same, depends on what you are making and how heavy you want the item to be. There is thinner yarn as tele mentioned, which is good for making doillies, thin shirts and such. I think one of the brands is Heart (if I remember correctly). I know in crocheting there is different sizes of needles, I believe there is in knitting too. You definitely should talk to someone in a craft and/or fabric store that is knowledgeable on knitting.