@batmann: The airplay chart is/was a summary of the most played tracks on American radio. The Hot 100 is the Billboard chart that combines radio airplay and single sales.
From when the Hot 100 began in 1958 until 1998, only songs that were released as singles (or cassingles or CD-singles) were eligible to chart on the Hot 100. And for nearly all that time that had very little impact on the charts, since nearly every act on radio wanted to sell singles.
But that also meant that a lot of songs we now think of as "hits" never made that chart. "Michelle" and "Lucy in the Sky with Diamonds" by the Beatles, "Stairway to Heaven" by Led Zeppelin, "Pinball Wizard" by Elton John, "Do the Bartman" by the Simpsons, "Into the Groove" by Madonna. These were the exceptions, and I'm sure jmsr525 could provide a hundred others from before the airplay chart was introduced in 1991.
But by the 1990s, the profit margin on single went down, and fewer were released. More and more songs that got radio play either weren't released as singles at all or not put on singles until radio play peaked, and only released for the purposed of getting on the Hot 100.
This resulted in the phenomenon of songs entering the Hot 100 at #1 on a fairly regular basis, something previously unheard of on the charts. Airplay would build until the song was in the top ten, then a limited quantity of singles would be released and the song became eligible for the Hot 100. The combination of high airplay and minimal sales was still enough to get a #1 song.
But by the mid-90s, record companies often forgoed (forwent?) releasing singles at all. No Doubt's "Don't Speak" spent months atop the airplay chart but was never eligible for the Hot 100. Neither was "Men In Black" or "Torn" or "LoveFool" or "Killing Me Softly". The Hot 100 was so distant from actual public tastes, that Billboard was forced to change the eligibility rules. As of the start of the new chart year in 1999 (Dec. 1998), songs could chart on airplay alone.
With the introduction |
VH1's 100 Songs ('90s) 
Top 10 Hits of 2009 
'90s TV Theme Songs
