Mainstream radio

Contemporary hit radio (also known as CHR, contemporary hits, hit list, current hits, hit music, top 40, or pop radio) is a radio format that is common in the United States, United Kingdom, Ireland, Canada, New Zealand, Australia, Singapore, Trinidad and Tobago and South Africa that focuses on playing current and recurrent popular music as determined by the top 40 music charts. There are several subcategories, dominantly focusing on rock, pop, or urban music. Used alone, CHR most often refers to the CHR-pop format. The term contemporary hit radio was coined in the early 1980s by Radio & Records magazine to designate top 40 stations which continued to play hits from all musical genres as pop music splintered into adult contemporary, urban contemporary and other formats.

The term "top 40" is also used to refer to the actual list of hit songs, and, by extension, to refer to pop music in general. The term has also been modified to describe top 50; top 30; top 20; top 10; hot 100 (each with its number of songs) and hot hits radio formats, but carrying more or less the same meaning and having the same creative point of origin with Todd Storz as further refined by Gordon McLendon as well as Bill Drake. The format became especially popular in the sixties as radio stations constrained disc jockeys to numbered play lists in the wake of the payola scandal.

Also known as CHR/pop or teen CHR. Plays pop, and dance, and sometimes urban, alternative, rock, and country crossover as well. Often referred as "top 40"; in terms of incorporating a variety of genres of music, CHR/pop is the successor to the original concept of top 40 radio which originated in the 1950s. WHTZ in New York City, KIIS in Los Angeles, KRBE in Houston, WBBM in Chicago, WFLZ in Tampa/St. Petersburg, WHYI in Miami, WNCI in Columbus, WZPL, in Indianapolis, KDWB in Minneapolis/St. Paul and D100 Radio (Internet/New York) are the best-known CHR/pop stations in the U.S. See also: Mainstream Top 40 (Pop Songs)

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