Music is generally defined as the art of arranging sound to create some combination of form, harmony, melody, rhythm, or otherwise expressive content. Definitions of music vary depending on culture, though it is an aspect of all human societies and a cultural universal. While scholars agree that music is defined by a few specific elements, there is no consensus on their precise definitions. The creation of music is commonly divided into musical composition, musical improvisation, and musical performance, though the topic itself extends into academic disciplines, criticism, philosophy, and psychology.
In a musical composition, a chord progression or harmonic progression (informally chord changes, used as a plural) is a succession of chords. Chord progressions are the foundation of harmony in Western musical tradition from the common practice era of Classical music to the 21st century. Chord progressions are the foundation of popular music styles (e.g., pop music, rock music), traditional music, as well as genres such as blues and jazz. In these genres, chord progressions are the defining feature on which melody and rhythm are built.
Bassline (also known as a bass line or bass part) is the term used in many styles of music, such as blues, jazz, funk, dub and electronic, traditional, or classical music for the low-pitched instrumental part or line played (in jazz and some forms of popular music) by a rhythm section instrument such as the electric bass, double bass, cello, tuba or keyboard (piano, Hammond organ, electric organ, or synthesizer).
A brass instrument is a musical instrument that produces sound by sympathetic vibration of air in a tubular resonator in sympathy with the vibration of the player's lips. Brass instruments are also called labrosones or labrophones, from Latin and Greek elements meaning 'lip' and 'sound'. There are several factors involved in producing different pitches on a brass instrument.
Chamber music is a form of classical music that is composed for a small group of instruments—traditionally a group that could fit in a palace chamber or a large room. Most broadly, it includes any art music that is performed by a small number of performers, with one performer to a part (in contrast to orchestral music, in which each string part is played by a number of performers). However, by convention, it usually does not include solo instrument performances.
Musical improvisation (also known as musical extemporization) is the creative activity of immediate ("in the moment") musical composition, which combines performance with communication of emotions and instrumental technique as well as spontaneous response to other musicians. Sometimes musical ideas in improvisation are spontaneous, but may be based on chord changes in classical music and many other kinds of music. One definition is a "performance given extempore without planning or preparation".
Basso continuo parts, almost universal in the Baroque era (1600–1750), provided the harmonic structure of the music by supplying a bassline and a chord progression. The phrase is often shortened to continuo, and the instrumentalists playing the continuo part are called the continuo group. The composition of the continuo group is often left to the discretion of the performers (or, for a large performance, the conductor), and practice varied enormously within the Baroque period.
Historically informed performance (also referred to as period performance, authentic performance, or HIP) is an approach to the performance of classical music, which aims to be faithful to the approach, manner and style of the musical era in which a work was originally conceived. It is based on two key aspects: the application of the stylistic and technical aspects of performance, known as performance practice; and the use of period instruments which may be reproductions of historical instruments that were in use at the time of the original composition, and which usually have different timbre and temperament from their modern equivalents.
The term string quartet can refer to either a type of musical composition or a group of four people who play them. Many composers from the mid-18th century onwards wrote string quartets. The associated musical ensemble consists of two violinists, a violist, and a cellist. The string quartet was developed into its present form by the Austrian composer Joseph Haydn, whose works in the 1750s established the ensemble as a group of four more-or-less equal partners.
The string section is composed of bowed instruments belonging to the violin family. It normally consists of first and second violins, violas, cellos, and double basses. It is the most numerous group in the standard orchestra. In discussions of the instrumentation of a musical work, the phrase "the strings" or "and strings" is used to indicate a string section as just defined. An orchestra consisting solely of a string section is called a string orchestra.
