Katakana(片仮名) is commonly used to write the following:
- transliteration of names and foreign words, like コンピュータ (konpyūta, “computer”) and ロンドン (Rondon, “London”). However, some external borrowings that have later become naturalized may be rendered in hiragana. For example, たばこ (tabako), meaning “tobacco.”
- commonly used names of plants and animals, like バラ (bara, “rose”) and トカゲ (tokage, “lizard”), as well as specific other scientific and technical terms, like mineral names
- occasionally, the names of miscellaneous other objects whose kanji are unique and rare, like ローソク (rōsoku, “candle”)
- onomatopoeia, like for example ワンワン (wan-wan, “woof-woof”), and other sound symbolism
- the emphasis, much like italicization in European languages.
Katakana can also be actively used to impart the idea that words are spoken in a foreign or unusual accent; for instance, the speech of a robot.