I love writing haiku.
Contrary to what many people believe, it is much more than a short poem written in three lines of 5 - 7 - 5 syllables. In fact, many English language poets have moved away from this misinterpreted rule. Contemporary poets even write one-line haiku.
For me, however, the true essence of haiku has nothing to do with the syllable count, or how many lines it is comprised of. It is more about the intrinsically calming effect of the process.
Writing haiku urges the poet to slow down and shift their awareness to the present moment. It fosters an appreciation for nature and of simple everyday moments. While for the reader, a well-crafted haiku can linger in the heart and mind like the soothing warmth of a cup of tea.
Many people today define haiku as a three-lined poem comprised of 17 syllables. It is true that traditional Japanese haiku followed the form of 5-7-5 sound units, but in Japan, sound units (called mora) are shorter and counted differently than English syllables.
For example, in English, the word London is counted as two syllables, but in Japanese, the word would be broken down in the following way: lo/n/do/n. (See Stalking the Wild Onji, by Richard Gilbert, PH.D.)
This means that if an English language haiku comprised of 17 syllables was translated into Japanese, it would be counted as having more than 17 Japanese sound units. This is why English language haiku that follow the 5-7-5 form can sometimes end up feeling wordy.