Toy trains were altered when Märklina German company which specialized in doll house accessories, sought to make an equivalent toy for boys in which a continuous revenue stream could be ensured by selling add-on accessories for decades after the initial purchase. In addition to boxed sets containing a train and track, Märklin offered additional track, rolling stock, and buildings offered separately, creating the predecessor to the modern model train layout featuring scenery and buildings in addition to a working train.
Electric trains adopted, with the first appearing in 1897, produced from the U.S. company Carlisle &amp; Finch. As residential use of electricity became more common in the early 20th century, electrical trains gained popularity and as time moved on, these electric trains grew in sophistication, gaining light, the ability to change management, to emit a whistling sound, to smoke, to remotely couple and uncouple cars as well as load and unload freight. Toy trains from the first half of the 20th century were often made of lithographed tin; afterwards trains were frequently made mainly of plastic.
Today, S gauge and O gauge railroads continue to be considered toy trains by their own adherents and are often accessorized with semi-scale model buildings by Plasticville or even K-Line (who owns the rights to the Plasticville-like buildings created by Marx from the 1950s into the 1970s). However, as a result of their high cost, one is more inclined to locate an HO scale or N scale train set at a toy shop than a O scale collection.
Many modern electric toy trains comprise sophisticated electronics that emit digitized sound effects and allow the operator to safely and easily run multiple remote controller trains on a single loop of track. In recent decades, many toy train operators may operate a train with a TV camera at the front part of the engine and hooked up to a screen, such as computer monitor. This will show an image, like that of a genuine (smaller size) railroad.