Key (music) in the context of "Chord chart"

An order in architecture is a certain assemblage of parts subject to uniform established proportions, regulated by the office that each part has to perform.Coming down to the present from Ancient Greek and Ancient Roman civilization, the architectural orders are the styles of classical architecture, each distinguished by its proportions and characteristic profiles and details, and most readily recognizable by the type of column employed. The three orders of architecture—the Doric, Ionic, and Corinthian—originated in Greece. To these the Romans added, in practice if not in name, the Tuscan, which they made simpler than Doric, and the Composite, which was more ornamental than the Corinthian. The architectural order of a classical building is akin to the mode or key of classical music; the grammar or rhetoric of a written composition. It is established by certain modules like the intervals of music, and it raises certain expectations in an audience attuned to its language.

Whereas the orders were essentially structural in Ancient Greek architecture, which made little use of the arch until its late period, in Roman architecture where the arch was often dominant, the orders became increasingly decorative elements except in porticos and similar uses. Columns shrank into half-columns emerging from walls or turned into pilasters. This treatment continued after the conscious and "correct" use of the orders, initially following exclusively Roman models, returned in the Italian Renaissance. Greek Revival architecture, inspired by increasing knowledge of Greek originals, returned to more authentic models, including ones from relatively early periods.

Atonality in its broadest sense is music that lacks a tonal center, or key. Atonality, in this sense, usually describes compositions written from about the early 20th century to the present day, where a hierarchy of harmonies focusing on a single, central triad is not used, and the notes of the chromatic scale function independently of one another. More narrowly, the term atonality describes music that does not conform to the system of tonal hierarchies that characterized European classical music between the seventeenth and nineteenth centuries. "The repertory of atonal music is characterized by the occurrence of pitches in novel combinations, as well as by the occurrence of familiar pitch combinations in unfamiliar environments".

The term is also occasionally used to describe music that is neither tonal nor serial, especially the pre-twelve-tone music of the Second Viennese School, principally Alban Berg, Arnold Schoenberg, and Anton Webern. However, "as a categorical label, 'atonal' generally means only that the piece is in the Western tradition and is not 'tonal'", although there are longer periods, e.g., medieval, renaissance, and modern modal music to which this definition does not apply. "Serialism arose partly as a means of organizing more coherently the relations used in the pre-serial 'free atonal' music. ... Thus, many useful and crucial insights about even strictly serial music depend only on such basic atonal theory".

The twelve-tone technique—also known as dodecaphony, twelve-tone serialism, and (in British usage) twelve-note composition—is a method of musical composition. The technique is a means of ensuring that all 12 notes of the chromatic scale are sounded equally often in a piece of music while preventing the emphasis of any one note through the use of tone rows, orderings of the 12 pitch classes. All 12 notes are thus given more or less equal importance, and the music avoids being in a key.

The technique was first devised by Austrian composer Josef Matthias Hauer, who published his "law of the twelve tones" in 1919. In 1923, Arnold Schoenberg (1874–1951) developed his own, better-known version of 12-tone technique, which became associated with the "Second Viennese School" composers, who were the primary users of the technique in the first decades of its existence. Over time, the technique increased greatly in popularity and eventually became widely influential on mid-20th-century composers. Many important composers who had originally not subscribed to or actively opposed the technique, such as Aaron Copland and Igor Stravinsky, eventually adopted it in their music.

In a musical composition, a chord progression or harmonic progression (informally chord changes, used as a plural, or simply changes) 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.

In tonal music, chord progressions have the function of either establishing or otherwise contradicting a tonality, the technical name for what is commonly understood as the "key" of a song or piece. Chord progressions, such as the extremely common chord progression I-V-vi-IV, are usually expressed by Roman numerals in classical music theory. In many styles of popular and traditional music, chord progressions are expressed using the name and "quality" of the chords. For example, the previously mentioned chord progression, in the key of E♭ major, would be written as E♭ major–B♭ major–C minor–A♭ major in a fake book or lead sheet. In the first chord, E♭ major, the "E♭" indicates that the chord is built on the root note "E♭" and the word "major" indicates that a major chord is built on this "E♭" note.

Baroque music (UK: /bəˈrɒk/ or US: /bəˈroʊk/) refers to the period or dominant style of Western classical music composed from about 1600 to 1750. The Baroque style followed the Renaissance period, and was followed in turn by the Classical period after a short transition (the galant style). The Baroque period is divided into three major phases: early, middle, and late. Overlapping in time, they are conventionally dated from 1580 to 1650, from 1630 to 1700, and from 1680 to 1750. Baroque music forms a major portion of the "classical music" canon, and continues to be widely studied, performed, and listened to. The term "baroque" comes from the Portuguese word barroco, meaning "misshapen pearl". Key composers of the Baroque era include Johann Sebastian Bach, George Frideric Handel, Henry Purcell, Antonio Vivaldi, Georg Philipp Telemann, Domenico Scarlatti, Claudio Monteverdi, Girolamo Frescobaldi, Alessandro Scarlatti, Jean-Baptiste Lully, Jean-Philippe Rameau, Arcangelo Corelli, François Couperin, Heinrich Schütz, Dieterich Buxtehude, and Heinrich Ignaz Franz Biber.

The Baroque saw the formalization of common-practice tonality, an approach to writing music in which a song or piece is written in a particular key; this type of harmony has continued to be used extensively in Western classical and popular music. During the Baroque era, professional musicians were expected to be accomplished improvisers of both solo melodic lines and accompaniment parts. Baroque concerts were typically accompanied by a basso continuo group (comprising chord-playing instrumentalists such as harpsichordists and lute players improvising chords from a figured bass part) while a group of bass instruments—viol, cello, double bass—played the bassline. A characteristic Baroque form was the dance suite. While the pieces in a dance suite were inspired by actual dance music, dance suites were designed purely for listening, not for accompanying dancers.

In Western musical notation, a key signature is a set of sharp (♯), flat (♭), or rarely, natural (♮) symbols placed on the staff at the beginning of a section of music. The initial key signature in a piece is placed immediately after the clef at the beginning of the first line. If the piece contains a section in a different key, the new key signature is placed at the beginning of that section.

In a key signature, a sharp or flat symbol on a line or space of the staff indicates that the note represented by that line or space is to be played a semitone higher (sharp) or lower (flat) than it would otherwise be played. This applies through the rest of the piece or until another key signature appears. Each symbol applies to comparable notes in all octaves—for example, a flat on the fourth space of the treble staff (as in the diagram) indicates that all notes notated as Es are played as E-flats, including those on the bottom line of the staff.

The chanter (Irish: seamsúr; Scottish Gaelic: seannsair; Scots: chanter, chaunter) is the part of the bagpipe upon which the player creates the melody. It consists of a number of finger-holes, and in its simpler forms looks similar to a recorder. On more elaborate bagpipes, such as the Northumbrian bagpipes or the Uilleann pipes, it also may have a number of keys, to increase the instrument's range and/or the number of keys (in the modal sense) it can play in. Like the rest of the bagpipe, they are often decorated with a variety of substances, including metal (silver/nickel/gold/brass), bone, ivory, or plastic mountings.