The modern Japanese writing system uses three main scripts:

1. Kanji, adopted Chinese characters

Kana a pair of syllabaries, consisting of:

2. Hiragana used along with kanji, for native or naturalised Japanese words and for grammatical events.

3. Katakana, used for foreign words and names, loanwords, onomatopoeia, scientific names and sometimes to replace kanji or hiragana for emphasis.

Balancing the three scripts in a nice and organised way can be difficult to do since the characters have such different styles.  But there are typographers out there who do it in a really clever and innovative way to get round this.