A refrigerator is a machine for keeping things cold. It is sometimes called a fridge or an icebox. People put food and drinks in it, to keep those items cold or good (unspoiled) for a longer time. A refrigerator has a heat pump. It takes heat away from the air inside the fridge. The heat gets added to the air outside. The heat pump is usually driven by an electric motor.
There are also ice boxes available that do not use electricity because they are filled with ice to provide the colder temperature. The ice can keep things cold until the ice melts. These ice boxes can be taken on camping trips. Sometimes they are called coolers. Refrigerator-sized iceboxes were used before electricity was available.
Most modern refrigerators are available in a variety of colours, although normally fridges are white, as shown in the picture. Smaller versions of the popular refrigerator are also used. These are mainly used in hotels and college dorm rooms.