Orchestration is the study or practice of writing music for an orchestra (or, more loosely, for any musical ensemble) or of adapting for orchestra music composed for another medium. It only gradually over the course of music history came to be regarded as a compositional art in itself.

The term orchestration in its specific sense refers to the way instruments are used to portray any musical aspect such as melody or harmony.

For example, a C major chord is made up of the notes C, E, and G. If the notes are held out the entire duration of a measure, the composer or orchestrator will have to decide what instrument(s) play this chord and in what register. Some instruments, including woodwinds and brass are primarily monophonic and can only play one note of the chord at a time. However in a full orchestra there is generally more than one of these instruments, so the composer may choose to outline the chord in its basic form with clarinets or trumpets. Other instruments, including the strings, piano, harp, and pitched percussion are polyphonic and may play more than one note at a time.

Leonard Bernstein ( /ˈbɜrnstaɪn/ US dict: bûrn′·stīn; August 25, 1918 – October 14, 1990) was an American composer, conductor, author, music lecturer and pianist. He was among the first conductors born and educated in the United States of America to receive worldwide acclaim. According to The New York Times, he was "one of the most prodigiously talented and successful musicians in American history."

His fame derived from his long tenure as the music director of the New York Philharmonic, from his conducting of concerts with most of the world's leading orchestras, and from his music for West Side Story, as well as Candide, Wonderful Town, On the Town and his own Mass.

Bernstein was also the first conductor to give numerous television lectures on classical music, starting in 1954 and continuing until his death. In addition, he was a skilled pianist, often conducting piano concertos from the keyboard.

As a composer he wrote in many styles encompassing symphonic and orchestral music, ballet, film and theatre music, choral works, opera, chamber music and pieces for the piano. Many of his works are regularly performed around the world, although none has matched the tremendous popular and commercial success of West Side Story.

Marie-Juliette Olga Lili Boulanger (21 August 1893 – 15 March 1918) was a French composer, the younger sister of the noted composer and composition teacher Nadia Boulanger.

A Parisian-born child prodigy, Boulanger's talent was apparent even at the age of two, when Gabriel Fauré (a friend of the family and later one of Boulanger's teachers) discovered she had perfect pitch. Her parents, both of whom were musicians themselves, encouraged their daughter's musical education. Her father was 77 years old when Lili was born and she became very attached to him. Her mother, Raissa Myshetskaya (Mischetzky), was a Russian princess who married her Paris Conservatoire teacher, Ernest Boulanger; grandfather Frédéric Boulanger had been a noted cellist, and grandmother Juliette a singer. Boulanger accompanied her ten-year-old sister Nadia to classes at the Paris Conservatoire before she was five, shortly thereafter sitting in on classes on music theory and studying organ with Louis Vierne; she also sang and played piano, violin, cello, and harp. Amongst her teachers were Marcel Tournier and Alphonse Hasselmans.

Kanye Omari West ( /ˈkɑːnjeɪ/; born June 8, 1977) is an American musician, film director and fashion designer. West first rose to fame as a producer for Roc-A-Fella Records, where he eventually achieved recognition for his work on Jay-Z's album The Blueprint, as well as hit singles for musical artists including Alicia Keys, Ludacris, and Janet Jackson. His style of production originally used pitched-up vocal samples from soul songs incorporated with his own drums and instruments. However, subsequent productions saw him broadening his musical palette and expressing influences encompassing '70s R&B, baroque pop, trip hop, arena rock, folk, alternative, electronica, synthpop, and classical music.

West released his debut album The College Dropout in 2004, his second album Late Registration in 2005, his third album Graduation in 2007, his fourth album 808s & Heartbreak in 2008, and his fifth album My Beautiful Dark Twisted Fantasy in 2010. West released a collaborative album, Watch the Throne with Jay-Z in 2011, which is the duo's first collaborative album. His five solo albums, all of which have gone platinum, have received numerous awards and critical acclaim. As of 2012, West has won a total of eighteen Grammy Awards, making him one of the most awarded artists of all-time. All albums have been very commercially successful, with My Beautiful Dark Twisted Fantasy becoming his fourth consecutive No. 1 album in the U.S. upon release. West has had 5 songs exceed 3 million in digital sales as of July 2011, with "Gold Digger" selling 3,086,000, "Stronger" selling 4,402,000, "Heartless" selling 3,742,000, "E.T." selling over 4,000,000 and "Love Lockdown" selling over 3,000,000 placing him third in overall digital sales of the past decade. He has sold over 30 million digital songs in the United States making him one of the best-selling digital artists of all-time.

John Roger Stephens (born December 28, 1978), better known by his stage name John Legend, is an American singer-songwriter and actor. He has won nine Grammy Awards, and in 2007, he received the special Starlight award from the Songwriters Hall of Fame.

Prior to the release of his debut album, Stephens' career gained momentum through a series of successful collaborations with multiple established artists. Stephens added his voice to those of other artists, assisting in them reaching chart-topper hits. He lent his voice to Kanye West's All of the Lights, on Slum Village's "Selfish" and Dilated Peoples' "This Way". Other artists included Jay-Z's "Encore", and he sang backing vocals on Alicia Keys' 2003 song "You Don't Know My Name" and Fort Minor's "High Road." Stephens played piano on Lauryn Hill's "Everything Is Everything."

Stephens was born on December 28, 1978, in Springfield, Ohio. He is the son of Phyllis, a seamstress, and John Mills, a factory worker and former National Guardsman. Throughout his childhood, Stephens was homeschooled on and off by his mother. At the age of four, he began playing the piano and at the age of seven, he performed with his church choir. When he was ten, his parents divorced, causing his mother to suffer a breakdown. At the age of 12, Stephens attended North High School, from which he graduated four years later. He graduated salutatorian.