My daughter never officially 'crawled'. She'd sit up, lean on her hands, and toss her tushy over. Sit up, lean on her hands, and toss her tushy over. It was never the hands and knees crawling. It concerned me to the point where I asked her pediatrician. He looked at me and said, "Does she get from point A to point B?" I said, "yes." He says, "She's fine, leave her alone." (She went from that to walking at 11 months.) It was cute. Wierd, but cute. And almost fifteen years later, she's still wierd, but cute.
Well, technically yes that is crawling and hands and knees is creeping. At least when I took childhood education classes (but that was 7 or 8 years ago so the definition may have changed by now-lol). But most people call what she's doing scooting or creeping and when she gets on hands and knees they call it crawling. :-)