scansion

The precise units of poetic meter, like rhyme, vary from language to language and between poetic traditions. Often it involves precise arrangements of syllables into repeated patterns called feet within a line. In English verse the pattern of syllable stress differentiates feet, so English meter is founded on the pattern of stressed and unstressed syllables. In Latin verse, on the other hand, while the metrical units are similar, not syllable stresses but vowel lengths are the component parts of meter. Old English poetry used alliterative verse, a metrical pattern involving varied numbers of syllables but a fixed number of strong stresses in each line. Meters in English verse, and in the classical Western poetic tradition on which it is founded, are named by the characteristic foot and the number of feet per line. Thus, for example, blank verse is unrhymed "iambic pentameter," a meter composed of five feet per line in which the kind of feet called iambs predominate. The origin of this tradition of metrics is ancient Greek poetry from Homer, Pindar, Hesiod, Sappho, and the great tragedians of Athens.