In the 1970s, FM radio stations were known for their dedication to album-oriented rock (AOR) and often featured "album hour" or "album side" segments in their programming. During these segments, DJs would play an entire album or a side of an album, uninterrupted by commercials or other distractions.
This was a significant departure from the more commercial, singles-driven format of AM radio, which tended to focus on playing hit songs and shorter tracks.
FM radio's emphasis on album-oriented programming was reflective of the changing music landscape of the 1970s, as many artists were releasing concept albums and experimenting with longer, more complex songs. Album-oriented programming gave listeners the opportunity to fully immerse themselves in an artist's work and experience the album as a cohesive artistic statement, rather than just a collection of singles.
Many iconic albums from the 1970s, such as Pink Floyd's "Dark Side of the Moon" and Led Zeppelin's "Physical Graffiti," were first introduced to listeners through FM radio's album-oriented programming, and these albums went on to become classics of the era.
But, album hour listeners with tape recorders would often capture a copy to play later. Record companies were of course were not thrilled with the practice, fearing it would dilute sales of physical copies.
At the time, retail music formats were limited to vinyl records, 8-track tapes and cassettes. Few 8-track recorders existed. Before the advent of better forms of Dolby noise reduction and headroom extension, the sound quality of cassettes was, due to physical limitations and slow tape speed, hissy and compressed.
Listeners with reel-to-reel tape machines could capture a copy fairly close to the source material, but without the convenience of portability offered by 8-track and cassette.
Since the practice of playing entire albums without interruption was not illegal, the best the record companies could hope for was that listeners would want, and eventually purchase, a better quality original.
The practice eventually fell out of favor, either from record company pressure, or from the realization that, if a listener didn't care for the album, they would just switch stations.
A decade or more later, record companies would again have to worry about copying when CDs arrived with their master recording-level quality and ease of dubbing to still-popular cassettes. The real problem still lay ahead, though, when the era of Napster made it clear music fans would still happily accept sub-CD quality-- if they could get it for free. And not have to wait for their local radio station to play it.
Today, music consumption through subscription or ad-supported streaming service, or via satellite radio has become the norm, as corporate-owned FM stations now seem to offer only cookie-cutter formats; shallow and repetitive playlists; and obnoxious advertising.