In the broadest sense, a piece of music is a play (instrumental or vocal), which is the result of compositional activity. It is characterized by internal completeness, individualized form and content, fixation of musical notation for the purpose of subsequent performance.
The musical work can be monophonic (melody and accompaniment) and polyphonic (polyphony, homophony). It can represent both an independent number, and be part of a certain cinematic or dramatic action. The peculiarity and uniqueness of each composer's creation is achieved by a number of expressive means, such as harmony, tempo, harmony, meter, dynamics, rhythm, melody.
The term "musical genre" is used to describe different works depending on their origin and mode of performance.
Long since various songs (round, ritual, labor, etc.) have accompanied the life of the people and inspired the soldiers to win. So there were numerous vocal genres. A characteristic feature of the songs is the repeated repetition of the melody, the main melody.
Romance is a genre of vocal music that appeared in the 19th century. This work for the singer with instrumental accompaniment.
Unlike the romance, choral compositions are intended for performance by a large singing group under accompaniment or a cappella (without accompaniment).
Cantata is a rather voluminous piece of music intended for the performance of a singer - a soloist (or choir) and an orchestra. The works of this genre were written for a long time in honor of any significant date and were solemn in nature. However, there are also lyrical, narrative cantatas.
The oratorio is a large musical and dramatic composition. It does not involve scenic action and is intended for performance by the choir, soloist and orchestra.
Opera is a musical and dramatic composition in which theatrical action and music are combined. The main feature of this genre is that the spoken language of actors is replaced by singing.
Instrumental genres of works were formed later vocal. They have an application value. Instrumental music accompanied parades, hikes, religious processions, city balls. In the 17th century, new genres, deeper in meaning and content, appeared.
Sonata is an instrumental piece that usually consists of three contrasting parts (fast-slow-fast). A little later in the work of L. Beethoven there are four-part works of this genre.
Symphony - a musical composition intended for performance by an entire symphony orchestra. Just like the sonata, this work in the classical version consists of three parts. It is distinguished by a large volume, multifaceted content and the availability of a melodic language.
Concert - a musical work intended for the performance of an orchestra and solo instrument. Most often, the works of this genre are written in a cyclical three-part form, but sometimes one can see one-part concerts.
This concept is characterized by the ratio of parts in the product. So, the two-part form consists of two sections, usually contrasting in nature. Three-part - from three, and the first and third parts are similar in melodic language and mood, and the middle - is contrasted to them. Variations are a modified repetition of the main motif (theme).
There are other musical forms, such as the rondo (the theme repeats itself in an unchanged form), cyclical (it consists of several independent parts united by a single idea) and free (found in modern music).