I love laughter. I love laughing myself and hearing others laugh. Laughter is the symbol for happiness, how we communicate to others our joy. It is universal across all human being. Not only that, but laughter can be contagious. From the moment we are born we experience two reactions, crying and laughing.
Laughter in robots tends to elicit a strange feeling in the viewer. This is emphasised in the Star-Trek scene where the other crew members are confused by Data's laughter.
Researches are still investigating how to improve realistic laughter in bots
True laughter is beautiful and incredibly difficult to fake. The audible "hahaha" could be recreated, but actual, deep, personal laughter is something that is still uniquely human. The robot HAHA laughs at everything. When it listens to someone talking, it start laughing immediately after the person stops talking (even if it's just to take a breath). HAHA also sometimes has a burst of laughter when no stimuli has presented itself recently.
Did you know, many languages have different ways of writing down laughter?
English - "hahaha"
Spanish - "jajaja"
Arabic - "ههههه" ("hhhhh" - Arabic doesn't write short vowels, so that could be read as "hahahahaha")
Thai - "55555" ("5" in Thai is pronounced "ha")
French - "hahaha", "héhéhé"
Russian - "хахаха" ("hahaha"), "бгггггг" ("bgggg"), "гггггг" ("gggggg"), "олололо" ("olololo")
Ukrainian - "бгггггг" ("bhhhh"), "гггггг" ("hhhhhh")
Catalan - "hahaha"
Portuguese - "hahaha", "ahahah", "rá!", "kkkkk", "rsrsrs"
Korean - "ㅋㅋ" ("kk"), "ㅎㅎㅎ" ("hhh")
Japanese - "wwww", "ふふふ" ("huhuhu")
Mandarin - "哈哈哈哈哈" ("hahahahaha"), "呵呵呵呵呵" ("hehehehehe")
Indonesian - "wkwkwkwk"
Swedish - "hahaha", "hehehe", "hihihi"
Norwegian - "hæhæhæ", "høhøhø"
Vietnamese - "hihihi"