The sleeping car or sleeper (often wagon-lit) is a railway passenger car that can accommodate all its passengers in beds of one kind or another, primarily for the purpose of making nighttime travel more restful. Theodore Tuttle Woodruff was the American inventor of the sleeper car.
The first such cars saw sporadic use on American railroads in the 1830s; they could be configured for coach seating during the day. Some of the more luxurious types have private rooms (fully and solidly enclosed rooms that are not shared with strangers).
The Cumberland Valley Railroad pioneered sleeping car service in the spring of 1839, with a car named "Chambersburg", between Chambersburg and Harrisburg, Pennsylvania. A couple of years later a second car, the "Carlisle", was introduced into service.
In 1857, the Wason Manufacturing Company of Springfield, Massachusetts – one of the United States' first makers of railway passenger coach equipment – produced America's first specifically designed sleeping car.
The man who ultimately made the sleeping car business profitable in the United States was George Pullman, who began by building a luxurious sleeping car (named Pioneer) in 1865. The Pullman Company, founded as the Pullman Palace Car Company in 1867, owned and operated most sleeping cars in the United States until the mid-20th century, attaching them to passenger trains run by the various railroads; there were also some sleeping cars that were operated by Pullman but owned by the railroad running a given train. During the peak years of American passenger railroading, several all-Pullman trains existed, including the 20th Century Limited on the New York Central Railroad, the Broadway Limited on the Pennsylvania Railroad, the Panama Limited on the Illinois Central Railroad, and the Super Chief on the Atchison, Topeka and Santa Fe Railway.