History of music videos

In 1894, sheet music publishers Edward B. Marks and Joe Stern hired an electrician called George Thomas along with other various performers to promote sales of their song "The Little Lost Child". Using a magic lantern, Thomas projected a series of still images on a screen simultaneous to live performances. This would become a popular form of entertainment known as the illustrated song, the first step toward music video.
The earliest music videos or music promos were filmed in the mid 1950’s, however, before then, as early as the 1920’s, films by animators such as Oskar Fischinger were accompanied by musical scores labeld ‘visual music’.

 In 1940 , Walt Disney released Fantasia , an animated film based around famous pieces of classical music.

While the history of music videos goes back to advent of film and sound, it wasn't until the 60s when they were made with some sort of regularity. The 60s was the same decade that the beatles, came about along with other artists who started to use music videos as a form of promotion for various songs. The creation of promotional films continued into the Seventies, but it would not be until the success of a video shot for Queen's "Bohemian Rhapsody" that the record companies would start shooting videos for nearly every single they released. In the late Seventies interest in music videos had grown to the point that entire TV shows devoted to music videos were developed. By 1981 the growing interest in music videos resulted in the creation of MTV( Music Televison), the first cable channel devoted entirely to music videos, which turned out to be an enormous success and grow to become a huge phenomenon in the 80s. The long-running British TV show Top of the Pops began playing music videos in the late 1970s, although the BBC placed strict limits on the number of 'outsourced' videos TOTP could use. Therefore a good video would increase a song's sales as viewers hoped to see it again the following week. In December 1992, MTV began listing directors with the artist and song credits, reflecting the fact that music videos had increasingly become an auteur's medium. Directors such as Michel Gondry, Spike Jonze, Stéphane Sednaoui, Mark Romanek and Hype Williams all got their start around this time; all brought a unique vision and style to the videos they directed.

Music videos are now becoming "Internet friendly", people are now watching videos on the internet on demand. Sites such as youtube count how many views a video has had, representing its popularity. Lady gaga's video for "Bad Romance" made headlines as youtubes most viewed video with over 350 million views in early 2011, however was over taken by Justin Beiber's song "Baby" with over 500 million views in early 2011.
  
Source: http://en.wikipedia.org/wiki/Music_video