Haiku
A brief poem of Japanese origin (traditionally 5-7-5), seizing a concrete instant, often anchored in a season.
The haiku is a brief Japanese form, brought to its summit by Bashō in the seventeenth century: traditionally seventeen morae in a 5-7-5 pattern, a season word (kigo) anchoring the instant in the year's cycle, and an internal cut (kireji) that makes two images collide. The poem doesn't comment: it shows a concrete instant, and meaning leaps from the juxtaposition.
Western adaptation turned syllabic 5-7-5 into a convenient but debated classroom convention — Japanese morae aren't our syllables, and many contemporary practitioners prefer free brevity faithful to the spirit: concision, concreteness, present tense, no commenting self. A royal exercise for any writer, poet or not: the haiku teaches you to cut everything that explains.
Example
The old pond — / a frog leaps in: / the sound of water.