Electric Refrigeration

With the development of the electric refrigerator in the 1920s, the icebox became a thing of the past. By pumping a special fluid that vaporizes at low temperatures through a system of pipes, the "fridge" became an indispensable household item that could store foods safely for longer periods. Today, fewer than 1 percent of American homes are without one.

Source: http://content.time.com/time/photogallery/0,29307,2026224,00.html