When you bring your camera from the cold outdoors to your heated house or car, you run the risk of condensation forming on your camera. That is very hazardous. If condensation occurs, open the memory compartments and battery compartments, take out everything not attached, and keep them open until they are dried out. Once the condensation happens, do NOT take your camera back outside. There is the possibility it will freeze, which will leave you with a very expensive neck adornment.
Another idea is to put your camera in a plastic bag while you’re still outside. The condensation will gather on the bag rather than on your camera. If you don’t have a plastic bag, let your camera warm up slowly. Keep it in the camera bag or leave it on a windowsill until it gets used to the temperature indoors. You can also use bags of rice which will take the condensation out of the air. If you’re traveling to a place which doesn’t allow food across the border, silica gel will also work.