Kaomoji

An emoticon (ee-MOHT-i-kon), (/ᵻˈmoʊtᵻkɒn/, or /iˈmoʊtᵻkɒn/) is a pictorial representation of a facial expression using punctuation marks, numbers and letters, usually written to express a person's feelings or mood.

In Western countries, emoticons are usually written at a right angle to the direction of the text. Users from Japan popularized a kind of emoticon called kaomoji (; lit. 顔(kao)=face, 文字(moji)=character(s); often confused with emoji in the West) that can be understood without tilting one's head to the left. This style arose on ASCII NET of Japan in 1986.

As social media has become widespread, emoticons have played a significant role in communication through technology, and some devices have provided stylized pictures that do not use punctuation. They offer another range of "tone" and feeling through texting that portrays specific emotions through facial gestures while in the midst of text-based cyber communication.

The word is a portmanteau word of the English words "emotion" and "icon". In web forums, instant messengers and online games, text emoticons are often automatically replaced with small corresponding images, which came to be called "emoticons" as well. Emoticons for a smiley face :-) and sad face :-( appear in the first documented use in digital form. Certain complex character combinations can only be accomplished in double-byte languages, giving rise to especially complex forms, sometimes known by their romanized Japanese name of kaomoji.

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Wikipedia