stylistic:style_transfer, linguistic:translation
A blueprint is a reproduction of a technical drawing or engineering drawing using a contact print process on light-sensitive sheets introduced by Sir John Herschel in 1842. The process allowed rapid and accurate production of an unlimited number of copies. It was widely used for over a century for the reproduction of specification drawings used in construction and industry. Blueprints were characterized by white lines on a blue background, a negative of the original. Color or shades of grey could not be reproduced. The process is obsolete, largely displaced by the diazo-based whiteprint process, and later by large-format xerographic photocopiers. It has almost entirely been superseded by digital computer-aided construction drawings. The term blueprint continues to be used informally to refer to any floor plan. Practising engineers, architects, and drafters often call them "drawings", "prints", or "plans".