So, instead of dog cages, other terms are used. Though, technically, they are all cages. Different terms are used to represent slightly different items. Dog kennels come in many sizes, and are generally set up outside for your dog. They are used for a variety of reasons. Some people use them regularly to keep their dog in because they do not have a fenced yard. Others use them occasionally when they do not want their dog running around the yard, perhaps when a young friend is over to play, or during a BBQ. For others, the kennel is a home, or safe place, for the dog. The kennel is often left open, and in there the dog can retreat, a place to call his own.
Dog crates are another form of dog cages. These are usually smaller, and kept in the house. In the house, they are also often used as a safe place which a dog can call his own. They are also great for travel, either in a car or truck, and necessary for airline travel. Crates come in many different styles, from traditional wire crates, to soft sided crates, folding crates, plastic crates, aluminum crates, and even wood crates that resemble a nice piece of furniture. There are many advantages to crate training a dog, and something I would highly recommend.
Dog boxes most resemble a cage, but are really a lot friendlier than they look. I had never heard of one of these until recently. They are aluminum boxes that are normally designed to be used in the back of a truck (some even mount in the truck like a tool box). Though there are obviously design difference, most resemble a metal box, many have solid sides than can be removed for ventilation (bars are revealed), they sometimes have storage in the top that is accessed through a lift lid. Some also have a bottom drawer, and top brands offer an integrated cooler design. These are designed to be a home away from home for dogs, and are often used by hunting dogs and competitive championship dogs. So given this, do not be deceived that they look like dog cages!