Japanese Input Method that comes with your computer is often equipped with generating special characters. Here are Windows-based examples. Similar conversion is probably available in other computer operating systems. After entering kana, keep hitting the space bar until you see other conversion options like the ones below. Hit the Enter key to finalize it.

You type:	What it means:	Hiragana:	Special characters:
migi	right	みぎ	→⇒
hidari	left	ひだり	←
ue	up	うえ	↑
sita	down	した	↓
maru	circle	まる	○◎●
sikaku	rectangle	しかく	◇◆□■
sankaku	triangle	さんかく	△▲▽▼
kakko	parentheses	かっこ	()[]{}〈〉《》「」『』【】""
hosi	star	ほし	★☆
enn	yen	えん	￥
doru	dollar	どる	＄
do	degree	ど	℃　°
onpu	musical notes	おんぷ	♪
sha-pu	sharp	しゃーぷ	♯
huratto	flat	ふらっと	♭
iti, ni, sann, ...	one, two, three, ...	いち, に, さん, ...	①②③...
kigou	symbol	きごう	all of the above and more

 

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