A haiku is a Japanese form of poetry in which the first line contains 5 syllables, the second line 7 syllables and the third line 5 syllables. Writing haiku involves adhering to many rules-or ignoring the rules-and then arguing with literary scholars about whether you've written a true haiku or not. Fortunately, reading a haiku is much easier than writing one.
Learn whether you are reading an original haiku written in English or a Japanese haiku that has been translated into English. If it is a translation, consider whether the translator kept the meaning at the expense of the meter or changed the meaning to keep the meter.
Remember that a haiku is about an abstract concept, usually an emotion, about nature. It describes a single moment as it forms in the poet's mind (a haiku moment).
Ask yourself what season is represented in the haiku, imaging the scene depicted in the poem.
Feel the emotion the haiku means to evoke. Remember that although the haiku might depict a scene in nature, you're meant to understand something about the human condition as well.
Note
Keep in mind that Japanese haiku is written in kanji, complex symbols that can represent more than one word. The Japanese language lends itself to phrases of 5 and 7 syllables very naturally, not only in haiku but in everyday life.