The hyakuin renga sequence begins with the hokku (), a 5-7-5 mora verse which was the origin of the late haiku genre. Unlike the following verses, the hokku in a renga session was expected to reflect the reality of the ba—its geographical location, season, etc.—and was also the only verse expected to be able to stand independently as a poem. The composition of the hokku was usually left to a skilled poet, and professional renga poets would sometimes be commissioned to write them during their travels. Often, the hokku would be written by the guest of the session, with the host responding with the second verse.Horton, H. Mack. “Renga Unbound: Performative Aspects of Japanese Linked Verse.” Harvard Journal of Asiatic Studies, vol. 53, no. 2, Harvard-Yenching Institute, 1993, pp. 443–512. JSTOR, JSTOR, doi:10.2307/2719455. Two technical conventions that carried over to haiku were the seasonal word kigo () and a “cutting word” kireji (). The hokku was followed by the wakiku (), daisan (), the names for the second and third verses respectively. Including these two, the rest of the linked verses were called tsukeku (), and verses 4-99 together were called the hiraku (). The final verse was called the ageku ().Jin’Ichi, Konishi, et al. “The Art of Renga.” Journal of Japanese Studies, vol. 2, no. 1, The Society for Japanese Studies, 1975, pp. 29–61. JSTOR, JSTOR, doi:10.2307/132038.
