Pajamas that are usually worn by children of toddler age up through 10 or so at the latest. Winter-wear, they either consist of a shirt and pants, or a one-piece jumpsuit. They are almost always made of a warm, soft material, usually cotton, flannel, or occasionally something somewhat like terrycloth What sets these apart from other pajamas, though, is the "footie" part--a white plastic foot attached to the ankles of the pamajas to keep feet warm. Usually lined with fleece on the inside and white, slick, and slightly knobbly on the outside (for traction), these keep a kid's foot warm while not slipping off or getting lost in the bed like socks. These are nice to wear when you're a small child. But beware the day you outgrow a pair by just a tiny bit. If they are too short in the least, they cause excruciating pain, including leg cramps, hurt toes, and any number of other ailments. That, and about the time you outgrow all the sizes these are made in, you've decided, in your pre-preteen rebellious sense, that you're WAY too cool for them anyways.