General conventions in Western poetry[edit]
Conventions that determine what might constitute line in poetry depend upon different constraints, aural characteristics or scripting conventions for any given language. On the whole, where relevant, a line is generally determined either by units of rhythm or repeating aural patterns in recitation that can also be marked by other features such as rhyme or alliteration, or by patterns of syllable-count.[3]
In Western literary traditions, use of line is arguably the principal feature which distinguishes poetry from prose. Even in poems where formal metre or rhyme is weakly observed or absent, the convention of line continues on the whole to be observed, at least in written representations, although there are exceptions (see Degrees of license). In such writing, simple visual appearance on a page (or any other written layout) remains sufficient to determine poetic line, and this sometimes leads to the suggestion that the work in question is no longer a poem but "chopped up prose".[4] A dropped line is a line broken into two parts, with the second indented to remain visually sequential.
In the standard conventions of Western literature, the line break is usually but not always at the left margin. Line breaks may occur mid-clause, creating enjambment, a term that literally means 'to straddle'. Enjambment "tend[s] to increase the pace of the poem",[5] whereas end-stopped lines, which are lines that break on caesuras (thought-pauses[6] often represented by ellipsis), emphasize these silences and slow the poem down.[5]
Line breaks may also serve to signal a change of movement or to suppress or highlight certain internal features of the poem, such as a rhyme or slant rhyme.
Line breaks can be a source of dynamism, providing a method by which poetic forms imbue their contents with intensities and corollary meanings that would not have been possible to the same degree in other forms of text.
Distinct forms of line, as defined in various verse traditions, are usually categorised according to different rhythmical, aural or visual patterns and metrical length appropriate to the language in question. (See Metre.)
One visual convention that is optionally used to convey a traditional use of line in printed settings is capitalisation of the first letter of the first word of each line regardless of other punctuation in the sentence, but it is not necessary to adhere to this. Other formally patterning elements, such as end-rhyme, may also strongly indicate how lines occur in verse.
In the speaking of verse, a line ending may be pronounced using a momentary pause, especially when its metrical composition is end-stopped, or it may be elided such that the utterance can flow seamlessly over the line break in what can be called run-on.
When verse is quoted within sentences in prose articles or critical essays, line breaks can be indicated by the forward slash (/); for example: "What in me is dark,/ Illumine, what is low raise and support,/ That to the height of this great argument/ I may assert eternal Providence,/ And justify the ways of God to men." (Milton, Paradise Lost). A stanza break can be indicated by the forward slash doubled (//).
Degrees of license[edit]
In more "free" forms, and in free verse in particular, conventions for the use of line become, arguably, more arbitrary and more visually determined such that they may only be properly apparent in typographical representation and/or page layout.
One extreme deviation from a conventional rule for line can occur in concrete poetry where the primacy of the visual component may over-ride or subsume poetic line in the generally regarded sense, or sound poems in which the aural component stretches the concept of line beyond any purely semantic coherence.
At another extreme, the prose poem simply eschews poetic line altogether.
In every type of literature there is a metrical pattern that can be described as "basic" or even "national". The most famous and widely used line of verse in English prosody is the iambic pentameter,[7] while one of the most common of traditional lines in surviving classical Latin and Greek prosody was the hexameter.[8] In modern Greek poetry hexameter was replaced by line of fifteen syllables. In French poetry alexandrine[9] is the most typical pattern. In Italian literature the hendecasyllable,[10] which is a metre of eleven syllables, is the most common line. In Serbian ten syllable lines were used in long epic poems. In Polish poetry two types of line were very popular, an 11-syllable one, based on Italian verse and 13-syllable one, based both on Latin verse and French alexandrine. Classical Sanskrit poetry, such as the Ramayana and Mahabharata, was most famously composed using the 32-syllable verse, derived from the Vedic anuṣṭubh metre called shloka.[11]
Pioneers of the freer use of line in Western culture include Whitman and Apollinaire.