は, in hiragana, or ハ in katakana, is one of the Japanese kana, each of which represent one mora. Both represent [ha]). They are also used as a grammatical particle (in such cases, they denote [wa], including in the greeting "kon'nichiwa") and serve as the topic marker of the sentence. は originates from 波 and ハ from 八. In the Sakhalin dialect of the Ainu language, the katakana ハ can be written as small ㇵ to represent a final h sound after an a sound (アㇵ ah). This, along with other extended katakana, was developed by Japanese linguists to represent sounds in Ainu not present in standard Japanese katakana.