What is the history of television?

The origins of what would become today's television system can be traced back to the discovery of the photoconductivity of the element selenium by Willoughby Smith in 1873, and the invention of a scanning disk by Paul Nipkow in 1884. The two inventions were first joined for practical use in the electronic transmission of still pictures and photographs, and by the first decade of the 20th century halftone photographs were being transmitted by telegraph and telephone lines as a newspaper service.