Billboard (stylized as billboard since 2013) is an American music and entertainment magazine published weekly by Penske Media Corporation. The magazine provides music charts, news, video, opinion, reviews, events, and style related to the music industry. 

Its music charts include the Hot 100, the 200, and the Global 200, tracking the most popular albums and songs in different genres of music. It also hosts events, owns a publishing firm, and operates several TV shows.

Billboard was founded in 1894 by William Donaldson and James Hennegan as a trade publication for bill posters. Donaldson later acquired Hennegan’s interest in 1900 for $500. In the early years of the 20th century, it covered the entertainment industry, such as circuses, fairs, and burlesque shows, and also created a mail service for travelling entertainers. 

Billboard began focusing more on the music industry as the jukebox, phonograph, and radio became commonplace. Many topics it covered were spun-off into different magazines, including Amusement Business in 1961 to cover outdoor entertainment, so that it could focus on music. 

After Donaldson died in 1925, Billboard was passed down to his children and Hennegan’s children, until it was sold to private investors in 1985, and has since been owned by various parties.

According to en.wikipedia; timetoast.com. Source of photos: internet