Haiku's are 3-line Japanese poems. Haiku's don't have to follow a certain rhyme-scheme, and the 1st and 3rd lines have 5 syllables, while the 2nd has 7. Haiku's tend to almost always be about nature. Some people who embraced the Haiku were Basho, Buson, and Issa.

A Ball of Snow by Matsuo Basho

you make the fire
and I’ll show you something wonderful:
a big ball of snow!