A parking lot (or car park) is an area where cars and other vehicles are parked and left temporarily. They are usually flat. The surface is usually made of asphalt, concrete, or gravel. Some lots may be bare earth. The paving material in a parking lot can heat quickly in the sun. A parked car can get hot, too. Children, older people, and animals such as dogs and cats should not be left in a parked car. They can die in a hot car.