foundation piecing and paper piecing are the same thin, and there is english paper piecing, but I don't really know the difference. I think one of them you sew through the paper, and the other you just fold it over and you can reuse the paper...
here are a couple of links to rag quilts and I spy quilts, they explain it better and in more detail that I could.
http://www.knitandtonic.typepad.com/SimpleRagQuilt.pdf
http://quilting.about.com/od/quiltin.../ispyquilt.htm
I don't know what sew and flip or folded quilts are, but you could just google it...