Title: Sleep (Eric Whitacre song)
Content:  Sleep is a work for a cappella chorus composed by Eric Whitacre with lyrics by poet Charles Anthony Silvestri.
Title: Sleep (album)
Content:  Sleep is an eight-and-a-half hour concept album based around the neuroscience of sleep by composer Max Richter. It was released in 2015, accompanied by a one-hour version with variations, From Sleep, and later remixed as Sleep Remixes.
Title: Sleep (album)
Content: Main personnel ; Max Richter – composer, electronics, liner notes, mixing, organ, piano, primary artist, producer, quotation author, synthesizer ; American Contemporary Music Ensemble – strings (ensemble) ; Grace Davidson – vocals (soprano) ; Brian Snow – cello ; Clarice Jensen – cello ; Caleb Burhans – viola ; Ben Russell – violin ; Yuki Numata Resnick – violin Additional personnel ; Christian Badzura – project manager ; Tom Bailey – assistant engineer ; Tim Cooper – liner notes ; Rupert Coulson – engineer, mixing ; David Eagleman – liner notes ; Merle Kersten – art direction ; Yulia Mahr – executive producer ; Mandy Parnell – mastering ; Anna-Lena Rodewald – project manager ; Mike Terry – photography ; Alejandro Venguer – engineer ; Mareike Walter – design  
Title: Sleep (album)
Content:  Sleep is targeted to fit a full night's rest. Richter talked with American neuroscientist David Eagleman while working on the album's piece to learn about how the brain functions during sleep. Richter stated, "Sleeping is one of the most important things we all do ... We spend a third of our lives asleep and it's always been one of my favourite things, ever since I was a child. ... For me, Sleep is an attempt to see how that space when your conscious mind is on holiday can be a place for music to live." The piece's 31 compositions, some 30 minutes in duration, are based around variations of 5 themes. The calm, slow and mellow composition is for piano, cello, two violas, two violins, organ, soprano vocals, synthesizers and electronics. In the album's credits Richter describes Sleep as an eight-hour lullaby and a piece that is meant to be listened to at night.
Title: The Science of Sleep
Content:  The score to The Science of Sleep was composed by Jean-Michel Bernard. Jean-Michel Bernard is a French pianist, composer, educator, orchestrator, and music producer. He is also well known for regularly writing, performing, and scoring film soundtracks. The song "Instinct Blues" by The White Stripes is used in the film but was not included on the soundtrack release. The song "If You Rescue Me", played by a band of people dressed as cats in a dream sequence, has the melody of the song "After Hours" by the Velvet Underground but with different lyrics.
Title: Sleepwalkers (film)
Content:  The original music score was composed by Nicholas Pike. (Side 2 of the cassette begins at track 9)
Title: Sleep (rapper)
Content:  Leading up to 2009, Sleep had contacted Sage Francis in an attempt to receive a feature for his upcoming album, which eventually led to his signing to Sage's independent label Strange Famous Records. In 2009, Sleep released his third solo album, Hesitation Wounds. It features verses from Grayskul and Del the Funky Homosapien as well as production from likes of Zavala and Reanimator, among others.
Title: Sleep (Eric Whitacre song)
Content:  Sleep has also been transcribed for concert band and string orchestra.
Title: Where Sleeplessness Is Rest from Nightmares
Content:  All music composed by Arma Angelus. All lyrics written by Pete Wentz.
Title: Sleep to Dream
Content:  The music video of the song was French director Stéphane Sednaoui and was released in May 1997. It features Apple singing in different rooms in an apartment, all the while suffering from insomnia.

Question: Who was the composer of Sleep?
Answer: Eric Whitacre.
Eric Edward Whitacre.