A theatre organ (also known as a theater organ, or, especially in the United Kingdom, a cinema organ) is a type of pipe organ developed to accompany silent films, from the 1900s to the 1920s. Theatre organs have horseshoe-shaped arrangements of stop tabs (tongue-shaped switches) above and around the instrument's keyboards on their consoles. Theatre organ consoles were typically decorated with brightly colored stop tabs, with built-in console lighting. Organs in the UK had a common feature: large translucent surrounds extending from both sides of the console, with internal colored lighting. Theatre organs began to be installed in other venues, such as civic auditoriums, sports arenas, private residences, and churches. One of the largest theatre organs ever built was the 6 manual 52 rank Barton installed in the Chicago Stadium. There were over 7,000 such organs installed in America and elsewhere from 1915 to 1933, but fewer than 40 instruments remain in their original venues. Though there are few original instruments, hundreds of theatre pipe organs are installed in public venues throughout the world today, while many more exist in private residences. Originally, films were accompanied by pit orchestras in larger houses, and pit pianists in small venues. The first organs installed in theatres were church organs. These organs were ill-suited to accompanying the film and the performance of popular tunes of the day. The earliest examples of the theatre organ concept were modified pianos with a few ranks of pipes and various sound effects, housed in one cabinet, and typically located in the pit area. These instruments were known as photoplayers. Robert Hope-Jones had a better idea, and his concept, which he called a "unit orchestra", was developed and promoted, initially by the Rudolph Wurlitzer Company of North Tonawanda, New York. The idea quickly caught on, and a new type of instrument, the Wurlitzer Hope Jones Unit-Orchestra or simply the theatre organ, was born.