A concept album is an album that tells a complete story through its songs, or follows a single theme, such as Pink Floyd's The Wall or Nick Cave's Murder Ballads. However, there are some artists who attempted to make concept albums, but only dedicated some songs to the concept, rather than all of them. Here are seven partial-concept albums.

1. The Beatles - Sgt. Pepper's Lonely Hearts Club Band (1967)

In addition to being cited as one of the greatest albums ever made, Sgt. Pepper's Lonely Hearts Club Band is often considered to be one of the very first concept albums, despite the fact that it only half-heartedly commits to its concept. Paul McCartney originally envisioned the album as an evening with the titular band, a concept that's pretty much abandoned after the first two tracks, and revisited once more towards the end. John Lennon even admitted that the concept "doesn't go anywhere...it works because we said it worked."

2. The Who - Who's Next (1971)

After the massive success of The Who's rock opera Tommy, guitarist Pete Townshend began work on another concept album titled Lifehouse, which was reportedly so complicated that nobody other than Townshend could understand it. When Lifehouse was eventually scrapped, many of the songs written for the project were used for The Who's next album Who's Next, which doesn't have an overarching narrative.

3. Frank Zappa - Apostrophe (') (1974)

Frank Zappa was no stranger to concept albums, having written the pop culture satire Freak Out! in 1966 and the hippie-skewering We're Only In It For The Money in 1968. His 1974 album Apostrophe (') follows a concept as well, telling the story of an Eskimo named Nanook, but only for the album's first side. The second side is mostly made up of pieces that Zappa had recorded during sessions for previous albums.

4. Pink Floyd - Wish You Were Here (1975)

Wish You Were Here isn't so much a "partial" concept album as it is one concept album sandwiched inside of another. Three of the album's tracks, "Shine On You Crazy Diamond, Parts I-V," "Wish You Were Here," and "Shine On You Crazy Diamond, Parts VI-IX," are tributes to Pink Floyd's original guitarist Syd Barrett, who had left the band in 1968 due to his mental health. The album's other two tracks, however, "Welcome to the Machine" and "Have A Cigar," are scathing critiques of the music business and record label executives.

5. Kate Bush - Hounds of Love (1985)

Driven by her dueling passions for pop songwriting and musical experimentation, Kate Bush divided her 1985 album Hounds of Love into two distinct halves. Side A contains five unrelated pop songs, while Side B is made up entirely of "The Ninth Wave," a song suite about a woman whose life flashes before her eyes as she drowns.

6. Alice in Chains - Dirt (1992)

According to Stereogum's article about Alice in Chains' Dirt, most of the album's second half was intended to be a concept piece about a drug addict and his descent into self-destruction, which is something that Alice in Chains fans know all too well, considering the tragic fate of lead vocalist Layne Staley.

7. The Flaming Lips - Yoshimi Battles the Pink Robots (2002)

Much like Sgt. Pepper's Lonely Hearts Club Band, the Flaming Lips' 2002 classic Yoshimi Battles the Pink Robots is often considered to be a concept album, despite the fact that only the album's first four tracks are related to the story of Yoshimi and the Pink Robots. However, this concept was strong enough to warrant a musical adaptation of the album.

What other albums only partially commit to their concepts? Let us know in the comments section!