The 24 Preludes and Fugues, Op. 87 by Dmitri Shostakovich are a set of 24 musical pieces for solo piano, one in each of the major and minor keys of the chromatic scale. The cycle was composed in 1950 and 1951 while Shostakovich was in Moscow, and premiered by pianist Tatiana Nikolayeva in Leningrad in December 1952; it was published the same year. A complete performance takes approximately 2 hours and 32 minutes. It is one of several examples of music written in all major or minor keys.

The 24 Preludes, Op. 34 is a set of short piano pieces written and premiered by Dmitri Shostakovich in 1933. They are arranged following the circle of fifths, with one prelude in each major and minor key.

"Dies irae" (Ecclesiastical Latin: [ˈdi.es ˈi.re]; "the Day of Wrath") is a Latin sequence attributed to either Thomas of Celano of the Franciscans (1200–1265) or to Latino Malabranca Orsini (d. 1294), lector at the Dominican studium at Santa Sabina, the forerunner of the Pontifical University of Saint Thomas Aquinas (the Angelicum) in Rome. The sequence dates from the 13th century at the latest, though it is possible that it is much older, with some sources ascribing its origin to St. Gregory the Great (d. 604), Bernard of Clairvaux (1090–1153), or Bonaventure (1221–1274). It is a medieval Latin poem characterized by its accentual stress and rhymed lines. The metre is trochaic. The poem describes the Last Judgment, the trumpet summoning souls before the throne of God, where the saved will be delivered and the unsaved cast into eternal flames. It is best known from its use in the Roman Rite Catholic Requiem Mass (Mass for the Dead or Funeral Mass). An English version is found in various Anglican Communion service books. The first melody set to these words, a Gregorian chant, is one of the most quoted in musical literature, appearing in the works of many composers. The final couplet, Pie Jesu, has been often reused as an independent song.

Dmitri Dmitriyevich Shostakovich (25 September [O.S. 12 September] 1906 – 9 August 1975) was a Soviet composer and pianist who became internationally known after the premiere of his First Symphony in 1926 and thereafter was regarded as a major composer. Shostakovich achieved early fame in the Soviet Union, but had a complex relationship with its government. His 1934 opera Lady Macbeth of Mtsensk was initially a success but later condemned by the Soviet government, putting his career at risk. In 1948, his work was denounced under the Zhdanov Doctrine, with professional consequences lasting several years. Even after his censure was rescinded in 1956, performances of his music were occasionally subject to state interventions, as with his Thirteenth Symphony (1962). Nevertheless, Shostakovich was a member of the Supreme Soviet of the RSFSR (1947) and the Supreme Soviet of the Soviet Union (from 1962 until his death), as well as chairman of the RSFSR Union of Composers (1960–1968). Over the course of his career, he earned several important awards, including the Order of Lenin, from the Soviet government. Shostakovich combined various musical techniques in his works. His music is characterized by sharp contrasts, elements of the grotesque, and ambivalent tonality; he was also heavily influenced by neoclassicism and by the music of Gustav Mahler. His orchestral works include 15 symphonies and six concerti (two each for piano, violin, and cello). His chamber works include 15 string quartets, a piano quintet, and two piano trios. His solo piano works include two sonatas, an early set of 24 preludes, and a later set of 24 preludes and fugues. Stage works include three completed operas and three ballets. Shostakovich also wrote several song cycles and a substantial quantity of music for theatre and film. Shostakovich's reputation has continued to grow after his death. Scholarly interest has increased significantly since the late 20th century, including considerable debate about the relationship between his music and his attitudes toward the Soviet government.

The 24 Preludes and Fugues, Op. 87 by Dmitri Shostakovich are a set of 24 musical pieces for solo piano, one in each of the major and minor keys of the chromatic scale. The cycle was composed in 1950 and 1951 while Shostakovich was in Moscow, and premiered by pianist Tatiana Nikolayeva in Leningrad in December 1952; it was published the same year. A complete performance takes approximately 2 hours and 32 minutes. It is one of several examples of music written in all major or minor keys.

Dmitri Shostakovich typically catalogued his compositions and occasionally his arrangements of other composers' music with opus numbers. He began this practice with the early Scherzo in F-sharp minor and continued until the end of his life. Nevertheless, most of his juvenilia, unfinished works from his artistic maturity (such as the operas Orango and The Gamblers), and numerous completed works were left unnumbered. There were also instances when Shostakovich took an opus number assigned to one work, then gave it to another, or was undecided about the numbering of a finished composition. Further complicating the matter was an error he committed in compiling his own music in the 1930s. This led to his soundtracks for The Youth of Maxim and Girl Friends sharing the same opus number.

Dmitri Shostakovich typically catalogued his compositions and occasionally his arrangements of other composers' music with opus numbers. He began this practice with the early Scherzo in F-sharp minor and continued until the end of his life. Nevertheless, most of his juvenilia, unfinished works from his artistic maturity (such as the operas Orango and The Gamblers), and numerous completed works were left unnumbered. There were also instances when Shostakovich took an opus number assigned to one work, then gave it to another, or was undecided about the numbering of a finished composition. Further complicating the matter was an error he committed in compiling his own music in the 1930s. This led to his soundtracks for The Youth of Maxim and Girl Friends sharing the same opus number.

Dmitri Shostakovich typically catalogued his compositions and occasionally his arrangements of other composers' music with opus numbers. He began this practice with the early Scherzo in F-sharp minor and continued until the end of his life. Nevertheless, most of his juvenilia, unfinished works from his artistic maturity (such as the operas Orango and The Gamblers), and numerous completed works were left unnumbered. There were also instances when Shostakovich took an opus number assigned to one work, then gave it to another, or was undecided about the numbering of a finished composition. Further complicating the matter was an error he committed in compiling his own music in the 1930s. This led to his soundtracks for The Youth of Maxim and Girl Friends sharing the same opus number.

Dmitri Shostakovich typically catalogued his compositions and occasionally his arrangements of other composers' music with opus numbers. He began this practice with the early Scherzo in F-sharp minor and continued until the end of his life. Nevertheless, most of his juvenilia, unfinished works from his artistic maturity (such as the operas Orango and The Gamblers), and numerous completed works were left unnumbered. There were also instances when Shostakovich took an opus number assigned to one work, then gave it to another, or was undecided about the numbering of a finished composition. Further complicating the matter was an error he committed in compiling his own music in the 1930s. This led to his soundtracks for The Youth of Maxim and Girl Friends sharing the same opus number.

The Piano Sonata No. 2 in B minor, Op. 61 by Dmitri Shostakovich, the last of his piano sonatas, was composed in early 1943. It was his first solo piano composition since 1933, as well as his second attempt at composing a piano sonata in the key of B minor. Shostakovich began composing the sonata while he and his family were evacuated in Kuybyshev (present-day Samara). A few months before, he heard about the death of his former piano teacher Leonid Nikolayev, which affected him profoundly; the sonata is dedicated to his memory. Originally, Shostakovich had planned a four-movement sonata in C-sharp minor, but by March 1943 had abandoned that idea in favor of the work's final three-movement form. Shostakovich premiered the sonata in Moscow on June 6, 1943. The sonata was received with mixed reviews. Ivan Sollertinsky felt it was one of the finest of all of Shostakovich's works. Emil Gilels, an important champion of the sonata, expressed disappointment and compared it unfavorably to Shostakovich's symphonies. Shostakovich himself was unsure of the work's quality; it was one of the few piano works from his maturity that he never recorded. Nevertheless, he told Inger Wikström in 1973 that he regarded the sonata as the most important of his piano works.

The Piano Sonata No. 2 in B minor, Op. 61 by Dmitri Shostakovich, the last of his piano sonatas, was composed in early 1943. It was his first solo piano composition since 1933, as well as his second attempt at composing a piano sonata in the key of B minor. Shostakovich began composing the sonata while he and his family were evacuated in Kuybyshev (present-day Samara). A few months before, he heard about the death of his former piano teacher Leonid Nikolayev, which affected him profoundly; the sonata is dedicated to his memory. Originally, Shostakovich had planned a four-movement sonata in C-sharp minor, but by March 1943 had abandoned that idea in favor of the work's final three-movement form. Shostakovich premiered the sonata in Moscow on June 6, 1943. The sonata was received with mixed reviews. Ivan Sollertinsky felt it was one of the finest of all of Shostakovich's works. Emil Gilels, an important champion of the sonata, expressed disappointment and compared it unfavorably to Shostakovich's symphonies. Shostakovich himself was unsure of the work's quality; it was one of the few piano works from his maturity that he never recorded. Nevertheless, he told Inger Wikström in 1973 that he regarded the sonata as the most important of his piano works.

F-sharp minor is a minor scale based on F♯, consisting of the pitches F♯, G♯, A, B, C♯, D, and E. Its key signature has three sharps. Its relative major is A major and its parallel major is F-sharp major (or enharmonically G-flat major). The F-sharp natural minor scale is: Changes needed for the melodic and harmonic versions of the scale are written in with accidentals as necessary. The F-sharp harmonic minor and melodic minor scales are: