In the American motion picture industry, a wide release (short for nationwide release) is a film playing at the same time at cinemas in most markets across the country. This is in contrast to the formerly common practice of a roadshow theatrical release in which a film opens at a few cinemas in key cities before circulating among cinemas around the country, or a limited release in which a film is booked at fewer cinemas (such as "art house" venues) in larger cities in anticipation of lesser commercial appeal. In some cases, a film that sells well in limited release will then "go wide". Since 1994, a wide release in the United States and Canada has been defined by Nielsen EDI as a film released in more than 600 theaters. The practice emerged as a successful marketing strategy in the 1970s, and became increasingly common in subsequent decades, in parallel with the expansion of the number of screens available at multiplex cinemas. With the switch to digital formats – lowering the added cost of wide release and increasing the opportunity for piracy – "opening wide" has become the default release strategy for big-budget mainstream films, sometimes expanding to include closely spaced wide releases in various countries, or even simultaneous world-wide release. History Prior to the 1980s, most feature films initially opened in major cities such as New York, Los Angeles, Paris, and London, with a small set of prints then circulating as a "roadshow" among cinemas regionally over the course of a few months. The number of prints in circulation would be increased only to accommodate demand for highly popular features, which might be "held over" beyond their originally scheduled run. Many of the most successful major releases during this period were handled this way. In 1946, David O. Selznick's Duel in the Sun was given a "blitz" release, where it was released simultaneously in a number of theaters in an area or city, with it opening in as many as 54 theaters in one area at the same time. The "blitz" approach had been used for a number of years in the Los Angeles area due to its geographic spread. Advantages of the new release approach included economies of scale on advertising costs and the fact that it allowed an old circus technique of making money and leaving before cinemagoers could realize how bad a film was. The following