Editing O scale (section)

==History==
The name for O gauge and O scale is derived from "0 [zero] gauge" or "Gauge 0" being smaller than [[Gauge 1]] and the other then-existing standards. It was created in part because manufacturers realized their best selling trains were those built in the smaller scales.

In the United States, manufacturers such as the [[Ives Manufacturing Company]], [[American Flyer]], and [[Lionel Corporation]] used O gauge for their budget line, marketing either Gauge 1 or 'Wide gauge' (also known as [[Standard Gauge (toy trains)|'standard gauge']]) as their premium trains. One of the Lionel Corporation's most popular trains, the 203 Armoured Locomotive, was O gauge and ran on tracks with rails spaced 1.25 inches apart. The [[Great Depression]] wiped out demand for the expensive larger trains, and by 1932, O gauge was the standard, almost by default.

Because of the emphasis on play value, the scale of pre–[[World War II]] O gauge trains varied. The Märklin specifications called for 1:43.5 scale. However, many designs were 1:48 scale or 1:64 scale. Early [[Louis Marx and Company|Marx Trains]] and entry-level trains, usually made of lithographed tin plate, were not scaled at all, made to whimsical proportions about the same length of an [[HO scale]] ("half O") piece, but about the same width and height of an O scale piece. Yet all of these designs ran on the same track, and, depending on the manufacturer(s) of the cars, could sometimes be coupled together and run as part of the same train.

After World War II, manufacturers started paying more attention to scale, and post-war locomotives and rolling stock tended to be larger and more realistic than their earlier counterparts. This has been reflected in the change of name from O ''gauge'' to O ''scale'': ''gauge'' describes merely the distance between the rails, while ''scale'' describes the size ratio of a model as it relates to its real-world [[prototype]].

Since the early 1990s, O scale manufacturers have begun placing more emphasis on realism, and the scale has experienced a resurgence in popularity, with manufacturers including [[Lionel, LLC|Lionel]], [[MTH Electric Trains|MTH]], [[Atlas Model Railroad|Atlas]], and [[Williams Electric Trains|Williams by Bachmann]] making O gauge model trains at 1:48 scale.

In the United Kingdom the dominant O gauge manufacturer before World War II was [[Meccano Ltd]]. who from 1920 produced a range of clockwork and electric models under the "Hornby" name.