So let’s see, what is “emoji”.
Emoji (絵文字?) is the Japanese term for the picture characters or emoticons used in Japanese electronic messages and webpages. Originally meaning pictograph, the word literally means e “picture” + moji “letter”. Some emoji are very specific to Japanese culture, such as a bowing (apologizing) businessman, a face wearing a face mask or a group of emoji representing popular foods (ramen, onigiri). The three main Japanese operators, NTT DoCoMo, au and SoftBank Mobile, have each defined their own variants of emoji.
We all know smileys started in the USA where the internet had also started of course. In Japan, the smileys(emoticons) grew in a different manner. Now, there are several kinds of them. Unlike western smileys, Japanese ones are read vertically, moreover Japanese smileys have more variation. The reason is, while American letters in computers are 1 byte, Japanese letters in computer are 2 bytes, so Japanese letters can have more characters.
1byte letters: ABCDabcd,.^=123456?+-*/=`@…….
2bytes letters : あいうえおカキクケコ＠１２３漢字♣♥〒♀♂ゞ∀≒ΩωЯф♪
Second reason seems to that Japanese comics(manga) have many ways of express their feelings, so Japanese are trying to do the same thing when they create smileys. So, a large number of Japanese smileys are influenced by comics.
So now, let’s see how Japanese smileys look like!
( ^_^)／ やぁ！
m(_ _)m ゴメンナサイ
These are my favorite smileys, but please, check out that site, there are thousands of Japanese emoji!