Couplet in the context of "Hark! The Herald Angels Sing"

A ballad is a form of verse, often a narrative set to music. Ballads were particularly characteristic of the popular poetry and song of Great Britain and Ireland from the Late Middle Ages until the 19th century. They were widely used across Europe, and later in Australia, North Africa, North America and South America.

While ballads have no prescribed structure and may vary in their number of lines and stanzas, many ballads employ quatrains with ${\displaystyle \mathrm {ABCB} }$ or ${\displaystyle \mathrm {ABAB} }$ rhyme schemes, the key being a rhymed second and fourth line. Contrary to a popular conception, it is rare if not unheard-of for a ballad to contain exactly 13 lines. Additionally, couplets rarely appear in ballads.

The octosyllable or octosyllabic verse is a line of verse with eight syllables. It is equivalent to tetrameter verse in trochees in languages with a stress accent. Its first occurrence is in a 10th-century Old French saint's legend, the Vie de Saint Leger; another early use is in the early 12th-century Anglo-Norman Voyage de saint Brendan. It is often used in French, Italian, Spanish and Portuguese poetry. While commonly used in couplets, typical stanzas using octosyllables are: décima, some quatrains, redondilla.

In Spanish verse, an octosyllable is a line that has its seventh syllable stressed, on the principle that this would normally be the penultimate syllable of a word (Lengua Castellana y Literatura, ed. Grazalema Santillana. El Verso y su Medida, p. 46). If the final word of a line does not fit this pattern, the line could have eight or seven or nine syllables (as normally counted), thus –

A madrigal is a form of secular vocal music most typical of the Renaissance (15th–16th centuries) and early Baroque (1580–1650) periods, although revisited by some later European composers. The polyphonic madrigal is unaccompanied, and the number of voices varies from two to eight, but the form usually features three to six voices, whilst the metre of the madrigal varies between two or three tercets, followed by one or two couplets. Unlike verse-repeating strophic forms sung to the same music, most madrigals are through-composed, featuring different music for each stanza of lyrics, whereby the composer expresses the emotions contained in each line and in single words of the poem being sung.

Madrigals written by Italianized Franco–Flemish composers in the 1520s partly originated from the three-to-four voice frottola (1470–1530); partly from composers' renewed interest in poetry written in vernacular Italian; partly from the stylistic influence of the French chanson; and from the polyphony of the motet (13th–16th centuries). The technical contrast between the musical forms is in the frottola consisting of music set to stanzas of text, whilst the madrigal is through-composed, a work with different music for different stanzas. As a composition, the madrigal of the Renaissance is unlike the two-to-three voice Italian Trecento madrigal (1300–1370) of the 14th century, having in common only the name madrigal, which some have suggested derives from the Latin matricalis (maternal) denoting musical work in service to the mother church or from the post-classical Latin matricalis (maternal, simple, primitive). Other sources note that the word "madrigal" comes from the Hebrew word "madriga" meaning "step" (the "-al" suffix of the word also is Hebrew, in this case meaning "in the style of") and describes the step-like progression of the tune. The early Christians having been Jews are believed to have brought the musical style into the Christian/Byzantine liturgy and, from there, into Gregorian chant and from there it made its way into secular song.

Mathnawi (/ˌmæθnəˈwiː/ MATH-nə-WEE), also spelled masnavi, mesnevi or masnawi, is a kind of poem written in rhyming couplets, or more specifically "a poem based on independent, internally rhyming lines". Most mathnawi poems follow a meter of eleven, or occasionally ten, syllables, but had no limit in their length. Typical mathnawi poems consist of an indefinite number of couplets, with the rhyme scheme aa/bb/cc.

Mathnawi poems have been written in Persian, Arabic, Turkish, Kurdish and Urdu cultures. Certain Persian mathnawi poems, such as Rumi's Masnavi, have had a special religious significance in Sufism. Other influential writings include the poems of Ghazali and ibn Arabi. Mathnawis are closely tied to Islamic theology, philosophy, and legends, and cannot be understood properly without knowledge about it.

In Chinese poetry, a duilian (simplified Chinese: 对联; traditional Chinese: 對聯; pinyin: duìlián) is a pair of lines of poetry which adhere to certain rules (see below). Outside of poems, they are usually seen on the sides of doors leading to people's homes or as hanging scrolls in an interior. Although often called Chinese couplet or antithetical couplet, they can better be described as a written form of counterpoint. The two lines have a one-to-one correspondence in their metrical length, and each pair of characters must have certain corresponding properties. A duilian is ideally profound yet concise, using one character per word in the style of Classical Chinese. A special, widely-seen type of duilian is the chunlian (simplified Chinese: 春联; traditional Chinese: 春聯; pinyin: chūnlián), used as a New Year's decoration that expresses happiness and hopeful thoughts for the coming year.

A bejtexhi (Albanian pronunciation: [bejted͡ʒi], lit. 'couplet maker', a compound of bejte [from Turkish beyit 'couplet', from Arabic بَيْت bayt] and -xhi [from Turkish -ci, occupational suffix]; plural: bejtexhinj [bejted͡ʒiɲ]) was a popular bard of the Muslim tradition in Ottoman Albania. The genre of literature created by bejtexhinj in the 18th century prevailed in different cities of what is now Albania, Kosovo, Chameria as well as in religious centers.

The spread of the bejtexhinj was a product of two different significant factors. One factor was a demand in religious practices to write in Albanian and to free it from foreign influence. The other factor was the accretion of ideological pressure from Turkish rulers. The ruling Ottomans sought the submission of Albanians through the Muslim religion and culture. Albania rulers opened their own schools with many bejtexhinj in attendance.

A bayt (Arabic: بَيْت, romanized: bayt, pronounced [bajt], lit. 'a house') is a metrical unit of Arabic, Azerbaijani, Ottoman, Persian, Punjabi, Sindhi and Urdu poetry.

In Arabic poetry, a bayt corresponds to a single line divided into two hemistichs of equal length, each containing two, three or four feet, or from 16 to 32 syllables. In Persian, Turkic and Urdu poetry, the word bayt has come to refer to two lines (like a couplet, although the two lines of a Persian, Turkic or Urdu bayt do not have to rhyme).